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16
Outcome of Planned Home and Hospital Births among Low-Risk Women in Iceland in 2005–2009: A Retrospective Cohort Study Berglind Halfdansdottir, RN, RM, MSc, Alexander Kr. Smarason, MD, DPhil, FRCOG, Olof A. Olafsdottir, RN, RM, MSc, PhD, Ingegerd Hildingsson, RN, RM, MSc, PhD, and Herdis Sveinsdottir, RN, MSc, PhD ABSTRACT: Background: At 2.2 percent in 2012, the home birth rate in Iceland is the highest in the Nordic countries and has been rising rapidly in the new millennium. The objective of this study was to compare the outcomes of planned home births and planned hospital births in comparable low-risk groups in Iceland. Methods: The study is a retrospective cohort study comparing the total population of 307 planned home births in Iceland in 2005–2009 to a matched 1:3 sample of 921 planned hospital births. Regression analysis, adjusted for confounding variables, was performed for the primary outcome variables. Results: The rate of oxytocin augmentation, epidural analgesia, and postpartum hemorrhage was significantly lower when labor started as a planned home birth. Differences in the rates of other primary outcome variables were not significant. The home birth group had lower rates of operative birth and obstetric anal sphincter injury. The rate of 5-minute Apgar score < 7 was the same in the home and hospital birth groups, but the home birth group had a higher rate of neonatal intensive care unit admission. Intervention and adverse outcome rates in both study groups, including transfer rates, were higher among primiparas than multiparas. Oxytocin augmentation, epidural analgesia, and postpartum hemorrhage rates were significantly interrelated. Conclusions: This study adds to the growing body of evidence that suggests that planned home birth for low-risk women is as safe as planned hospital birth. (BIRTH 42:1 March 2015)
Key words: midwifery, outcome, planned home birth, planned hospital birth
Observational studies on the outcome of home birth in Western societies have become more frequent in recent years and of greater methodological quality (1), increasing the scientific knowledge on the safety of home birth. Studies from different countries such as the United States, Canada, the United Kingdom, the Netherlands, Norway, Sweden, Australia, and New Zealand
indicate that maternal outcome is equally good or better in home birth than in hospital birth settings, with significantly less intervention (2–12) and morbidity (2,3,5,6,8–11,13,14), except for more frequent prolonged labor (5,7). Results on neonatal outcomes in home birth are less consistent: Some studies, predominantly from the United States, indicate that severe
Berglind Halfdansdottir is a Doctoral Student of Midwifery at Faculty of Nursing, School of Health Sciences, University of Iceland, Reykjavik, Iceland; Alexander Kr. Smarason is a Professor at School of Health Sciences, University of Akureyri, Akureyri, Iceland; Olof A. Olafsdottir is an Assistant Professor of Midwifery at Faculty of Nursing, School of Health Sciences, University of Iceland, Reykjavik, Iceland; Ingegerd Hildingsson is a Professor of Nursing Sciences at Department of Nursing, Mid Sweden University, Sundsvall, Sweden; Herdis Sveinsdottir is a Professor of Nursing at Faculty of Nursing, School of Health Sciences, University of Iceland, Reykjavik, Iceland.
Address correspondence to Berglind Halfdansdottir, RN, RM, MSc, Faculty of Nursing, School of Health Sciences, University of Iceland, Reykjavik, Eirbergi, Eirıksg€otu 34, Iceland.
Accepted November 25, 2014
© 2015 Wiley Periodicals, Inc.
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neonatal morbidity and mortality are significantly more likely in home than in hospital births (4,5,7,8,12,15– 17), while other studies from the United States, Canada, the Netherlands, Australia, and New Zealand describe either similar or better outcomes on neonatal morbidity, mortality, or need for medical assistance (6– 10,12,15,18,19). Information on the outcome of childbirth services is an essential part of a childbearing woman’s autonomy. Respect for a woman’s right to informed choice in place of birth is mirrored in health professionals’ duty to provide information applicable to the woman’s situation (20,21). Differences in home birth outcome may reflect underlying differences in the way home birth services are organized and regulated. When the results of previous studies are not generalizable to a given population, localized studies are important to maintain informed choice. The home birth rate in Iceland is the highest among the Nordic countries. Following a historical low of 0.1 percent in the 1990s (22), the rate has been rising rapidly in the new millennium, reaching 2.2 percent in 2012 (23). This study is the first to examine the outcome of home births in Iceland. Its purpose is to facilitate women’s informed choice in place of birth, to support further development of childbirth services, and to add to the growing body of international knowledge on home birth in the context of setting. The aim of the study is to answer two research questions: What is the outcome of planned home births in Iceland; and are there significant differences between the outcomes of planned home births and planned hospital births in comparable low-risk groups in that country?
Methods This study is a retrospective cohort study on the relationship between an independent variable—place of birth—and various dependent outcome variables. The study was approved by six regional health care authorities, 22 independent midwives, the Icelandic Data Protection Authority (no. PV2010/381), and the National Bioethics Committee (no. 10-064-S1). The study setting was in Iceland, a country with harsh terrain and unpredictable weather, a population of 325,000 and a low population density, conditions which can result in difficult long-distance traveling before or during labor. At 2.20 in 2010, Iceland’s fertility rate is the highest in Europe, and its home birth rate is the third highest for the same region, ranking only behind the Netherlands and the United Kingdom (24). In the capital area of Reykjavik, where 64 percent of the total population resides and where the country’s only tertiary hospital is located, 75 percent of home and hospital
births in Iceland take place (23). During the time of the study (2005–2009), the tertiary hospital was furnished with two birthing units, a high-risk obstetric unit and a low-risk alongside midwifery unit. In rural areas during the same period, one secondary and four primary hospitals offered services to low-, medium-, or high-risk women, in addition to the services of four low-risk units and home birth services (23,25). Home and hospital births in Iceland are attended to by midwives who obtain a license to practice after a 4year bachelor’s of science course in nursing and an additional 2-year master-level course in midwifery. The independent practices of home birth midwives are publicly funded (25) and are regulated and supervised by the Icelandic Directorate of Health, which has issued national guidelines for choice in place of birth. Contraindications for home birth and indications for intrapartum transfer are listed in the guidelines (25,26). An Icelandic electronic birth registry, commissioned and supervised by the Directorate of Health, is lacking data that would enable researchers to differentiate between planned and unplanned home births, or identify planned home births that end in hospital after transfer (25). It also lacks important outcome variables and confounders, such as the amount or severity of bleeding after birth, body mass index, and smoking. The information for the study’s database was therefore collected directly by the first author from the midwives’ and doctors’ original hand-written maternity notes, stored in various urban and rural locations. A structured item list of predefined variables and their values was used to ensure data collection completeness and homogeneity. For comparative purposes, the list was partially based on an item list used in a Norwegian study on home birth (3). The structured item list was translated and localized and the variables conceptualized and operationalized in an Icelandic pilot study (27). Data from the electronic birth registry were used for three planned home births for which all or some maternity notes were missing. Iceland’s small absolute numbers of births and midwives made it possible to contact every practicing home birth midwife directly. Thus, the total population of 307 planned home births accepted for midwifery care in Iceland at the onset of labor in 2005–2009 were included in this study, regardless of eventual place of birth (i.e., home births ending in hospital after transfer were included, while unplanned and unattended home births were excluded). The control group consisted of a purposive sample of 921 hospital births planned in the tertiary hospital (obstetric or alongside midwifery unit) or the rural secondary hospital. The control group was matched on parity (primipara vs multipara); contraindications (if present in the home birth); residence (capital vs rural, by transfer
BIRTH 42:1 March 2015
18 time to hospital); maternal age ( 2 years); and year of birth (next in chronological order) in a 1:3 ratio, resulting in a total n = 1,228. Controls with any of 67 predefined contraindications (supporting information), based on the Directorate of Health’s guidelines for home births, were excluded when matching low-risk home births without contraindications. Home births that were planned in spite of such contraindications were matched with controls with the same contraindications when possible; otherwise, they were matched with controls with no contraindications. The independent variable of the study—planned place of birth at the onset of labor—divided the study group into the home birth group and the hospital birth group. The primary dependent outcome variables were operative birth (instrumental or cesarean), oxytocin augmentation, epidural analgesia, bleeding after birth (continuous variable), and postpartum hemorrhage (three dichotomous categorical variables: ≥ 500, ≥ 800, and ≥ 1,000 mL), obstetric anal sphincter injury (OASI), neonatal intensive care unit (NICU) admission, and 5-minute Apgar scores < 7. Characteristics of participants and secondary dependent outcome variables are listed in Tables 1 and 2, respectively. Characteristics of participants were analyzed using t tests for continuous variables, Fisher exact test for the presence of a midwife, and chi-squared for other categorical variables (Table 1). Linear regression analysis for continuous primary outcome variables and logistic regression analysis for categorical primary outcome variables was performed on SPSS 21 (Table 3). Backwards selection of potential confounders was performed by testing models for six outcome variables with relatively high incidence. The regression model included nine confounders that significantly improved the model (maternal age; period of gestation; fetal presentation; water birth; smoking; birthweight; gender; parity; previous instrumental births). Sensitivity analysis was performed by running two separate models, adding confounders with high numbers of missing values (occupation; duration of labor). The study had two main approaches: 1) the natural prospective approach (intention to treat), including all home births and all matching hospital births, some with known contraindications; and 2) the perfect guideline approach (per protocol), including only low-risk home births and their matches. The approaches were further stratified by parity.
Results The natural prospective approach included 1,228 births. For the perfect guideline approach, 29 home births that were planned in spite of contraindications
and their 87 matches were excluded, leaving 1,112 births. Characteristics of participants in relation to place of birth are described in Table 1. Women planning home birth were significantly more likely to be married with a high occupational status. Home birth multiparas were significantly more likely to have had a previous home birth and they had a higher mean number of previous births. Home births had a significantly shorter first stage of labor, but a longer third stage and gestation period. They were significantly more likely to be water births and less likely to have a midwife present at the birth of the baby (as a result of precipitous labor); midwives were present at 98.4 percent of home births, and all hospital births. Home birth neonates were significantly less likely to have congenital anomalies, ranging from mild to severe. The study had no incidences of maternal or neonatal mortality (Table 2). The home birth group had lower rates of operative birth (both instrumental and cesarean), oxytocin augmentation, and epidural analgesia, compared with the hospital birth group. Women in the home birth group had lower rates of postpartum hemorrhage, OASI, episiotomy, cervical tear, blood transfusion, and morbidity in the first week postpartum, but a higher rate of vaginal tears, compared with women in the hospital birth group. Neonates in the home birth group had the same rates of 5-minute Apgar score < 7 as neonates in the hospital birth group. Neonates in the home birth group had higher rates of NICU admission and neonatal resuscitation, but lower rates of morbidity in the first week postpartum. Intervention and adverse outcome rates in both study groups were higher among primiparas than multiparas (Table 2). Transfer rates were also higher among primiparas than multiparas, but were not clinically comparable between the study groups because the indications for transfer were not the same in home and hospital births (26). Logistic regression on oxytocin augmentation, epidural analgesia, and postpartum hemorrhage as a categorical variable (≥ 500 mL [crude and adjusted] and ≥ 800 mL [crude]) revealed significantly lower odds ratios (ORs) in home births than in hospital births (Table 3), indicating that these interventions and adverse outcomes were significantly less frequent in the home birth group. Linear regression on bleeding after birth as a continuous variable also predicted significantly reduced bleeding in home birth, with differences between home and hospital birth ranging from 77 to 114 mL between models. The study lacked sufficient power (p = 1 b = 0.8) to detect differences in primary outcome variables with low incidences, such as operative birth (instrumental or cesarean), postpartum hemorrhage ≥ 1,000 mL, OASI, NICU admission, and 5-minute Apgar score < 7.
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Table 1. Characteristics of Low-Risk Women Having Planned Home and Hospital Births in Iceland, 2005–2009
Demographic Age, mean SD/n (%) < 25 25–34 ≥ 35 Year of birth, n (%) 2005 2006 2007 2008 2009 Residence, n (%) Capital (all ≤ 20 min) Rural ≤ 20 min Rural ˃ 20 ≤ 60 min Rural ˃ 60 min Marital status, n (%) Married Cohabiting Single Missing Occupation,* n (%) Specialist Semispecialist Nonspecialist Missing Citizenship, n (%) Icelandic Non-Icelandic Missing Clinical Parity, mean SD/n (%) Primipara Multipara Previous home births, n (%) No Yes Missing Previous instrumental births, n (%) No Yes Missing Body mass index, mean SD/n (%) < 25 25–29.99
All n = 1,228
Planned Home n = 307
Hospital n = 921
30.3 4.7 136 (11.1) 857 (69.8) 235 (19.1)
30.6 4.9 33 (10.7) 202 (65.8) 72 (23.5)
30.2 4.7 103 (11.2) 655 (71.1) 163 (17.7)
p 0.120
0.084
150 170 253 276 379
(12.2) (13.8) (20.6) (22.5) (30.9)
41 42 62 67 95
(13.4) (13.7) (20.2) (21.8) (30.9)
109 128 191 209 284
(11.8) (13.9) (20.7) (22.7) (30.8)
0.968
931 196 56 45
(75.8) (16.0) (4.6) (3.7)
232 50 14 11
(75.6) (16.3) (4.6) (3.6)
699 146 42 34
(75.9) (15.9) (4.6) (3.7)
0.998
505 (41.2) 650 (53.0) 72 (5.9) 1
143 (46.6) 156 (50.8) 8 (2.6) 0
362 (39.3) 494 (53.7) 64 (7.0) 1
569 (56.1) 304 (30.0) 142 (14.0) 213
170 (59.4) 89 (31.1) 27 (9.4) 21
399 (54.7) 215 (29.5) 115 (15.8) 192
1,085 (91.2) 105 (8.8) 38
286 (93.8) 19 (6.2) 2
799 (90.3) 86 (9.7) 36
1.24 0.93 256 (20.8) 972 (79.2)
1.40 1.08 64 (20.8) 243 (79.2)
1.18 0.87 192 (20.8) 729 (79.2)
1,155 (94.3) 70 (5.7) 3
235 (77.0) 70 (23.0) 2
1,088 (88.8) 137 (11.2) 3 25.0 4.3 676 (56.9) 356 (30.0)
275 (90.2) 30 (9.8) 2 24.8 4.1 171 (59.2) 88 (30.4)
920 (100.0) 0 (0.0) 1 813 (88.4) 107 (11.6) 1 25.1 4.4 505 (56.2) 268 (29.8)
0.005
0.032
0.064 0.002 1.000
< 0.001
0.389 0.291
(continued)
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20 Table 1 (continued)
All n = 1,228 ≥ 30 Missing Smoking, n (%) No Little Missing Mental health problems, n (%) No Yes Contraindications,† n (%) No Yes Birth-related Gestation, days (mean SD) Birthweight, g (mean SD) SGA, n (%) No Yes Congenital anomalies, n (%) No Yes Gender, n (%) Girl Boy Duration of labor (mean SD) Stage 1 Stage 2 Stage 3 Missing‡ Midwife present, n (%) No Yes Fetal presentation, n (%) Occupito-Anterior Occupito-Posterior Other Water birth, n (%) No Yes
Planned Home n = 307
Hospital n = 921
p
156 (13.1) 40
30 (10.4) 18
126 (14.0) 22
0.276
1,189 (97.1) 35 (2.9) 4
294 (97.0) 9 (3.0) 4
895 (97.2) 26 (2.8) 0
1,175 (95.7) 53 (4.3)
290 (94.5) 17 (5.5)
885 (96.1) 36 (3.9)
0.224
1,129 (91.9) 99 (8.1)
278 (90.6) 29 (9.4)
851 (92.4) 70 (7.6)
0.304
281.4 7.4 3,764 475
282.4 7.6 3,788 500
281.1 7.3 3,757 466
0.008 0.322
1,186 (96.6) 42 (3.4)
297 (96.7) 10 (3.3)
889 (96.5) 32 (3.5)
0.856
1,171 (95.4) 57 (4.6)
300 (97.7) 7 (2.3)
871 (94.6) 50 (5.4)
0.023
622 (50.7) 606 (49.3) 08:00 5:01 07:19 4:53 00:31 0:34 00:12 0:13 228
162 (52.8) 145 (47.2) 07:29 5:02 06:48 4:52 00:30 0:39 00:17 0:19 45
460 (49.9) 461 (50.1) 08:11 4:59 07:30 4:53 00:32 0:32 00:10 0:10 183
5 (0.4) 1,223 (99.6)
5 (1.6) 302 (98.4)
0 (0.0) 921 (100.0)
0.001
1,120 (91.2) 76 (6.2) 32 (2.6)
284 (92.5) 16 (5.2) 7 (2.3)
836 (90.8) 60 (6.5) 25 (2.7)
0.646
1,046 (85.2) 182 (14.8)
187 (60.9) 120 (39.1)
859 (93.3) 62 (6.7)
< 0.001
0.894
0.392 0.055 0.047 0.348 < 0.001
Percentages may not add up to 100 because of rounding. *Categorized using the Statistic Iceland‘s ISTARF95 classification system (based on the ISCO-88 International Standard Classification of Occupations). Variable values are proxies for Icelandic primary, secondary, and university education. †Predefined contraindications (supporting information) present in the study population: Hypertensive disorders; previous cesarean delivery; isoimmunization; prolonged pregnancy; hyperthyroidism; bipolar affective disorder; abnormal findings on antenatal screening; macrosomia or anticipated maternal–fetal disproportion; Body Mass Index > 35 or < 18. ‡Missing for any stage. Mean duration of stages does not add up to mean duration of labor because of differences in missing values. SGA = small for gestational age.
Primary outcomes Birth Method of delivery, n (%) Spontaneous vaginal birth Instrumental birth Cesarean birth Oxytocin augmentation, n (%) Epidural analgesia, n (%) Maternal Bleeding after birth (mL) (mean SD) Postpartum hemorrhage ≥ 500 mL n (%) Postpartum hemorrhage ≥ 800 mL n (%) Postpartum hemorrhage ≥ 1,000 mL n (%) Missing OASI, n (%) Neonatal NICU admission, n (%) 5-minute Apgar < 7, n (%) Secondary outcomes Birth Transfers, n (%) Transfer indication, n (%) Increased pain relief needed Prolonged labor, stimulation needed Other Urgent transfers, n (%) Transfer timing* (mean SD) Maternal Episiotomy, n (%) Vaginal tear, n (%) 66 (5.4) 17 (1.4)
14 (4.6) 6 (2.0)
(3.6) (6.5) (7.8) (0.0) 3:55
(10.9) (15.6) (12.5) (0.0) 4:06 9 (14.1) 2 (3.1)
7 10 8 0 6:19
25 (39.1)
55 (17.9) 11 20 24 0 4:55
12 (18.8) 4 (6.3)
(81.3) (10.9) (7.8) (26.6) (21.9)
400 307 16 (25.0) 4 (6.3) 4 (6.3) 0 4 (6.3)
52 7 5 17 14
22 (7.2) 5 (1.6)
(93.8) (3.9) (2.3) (8.8) (8.5)
85 (6.9) 20 (1.6)
288 12 7 27 26
Primipara n = 64
288 240 39 (12.9) 11 (3.6) 9 (3.0) 5 8 (2.6)
(92.8) (4.4) (2.8) (22.0) (18.6)
All n = 307
Planned Home
349 259 214 (17.6) 64 (5.3) 43 (3.5) 13 36 (2.9)
1,140 54 34 270 228
n = 1,228
All
(97.1) (2.1) (0.8) (4.1) (4.9)
(1.6) (4.1) (6.6) (0.0) 3:24 5 (2.1) 4 (1.6)
4 10 16 0 3:45
30 (12.3)
10 (4.1) 1 (0.4)
258 209 23 (9.7) 7 (2.9) 5 (2.1) 5 4 (1.6)
236 5 2 10 12
Multipara n = 243
Table 2. Birth Outcomes of Low-Risk Women Having Planned Home and Hospital Births in Iceland, 2005–2009
(92.5) (4.6) (2.9) (26.4) (21.9)
52 (5.6) 11 (1.2)
63 (6.8) 15 (1.6)
369 262 175 (19.2) 53 (5.8) 34 (3.7) 8 28 (3.0)
852 42 27 243 202
All n = 921
(80.2) (12.5) (7.3) (51.0) (51.0)
27 (14.1) 8 (4.2)
23 (12.0) 6 (3.1)
455 317 67 (35.3) 22 (11.6) 15 (7.9) 2 12 (6.3)
154 24 14 98 98
Primipara n = 192
Hospital
(95.7) (2.5) (1.8) (19.9) (14.3)
(continued)
25 (3.4) 3 (0.4)
40 (5.5) 9 (1.2)
346 240 108 (14.9) 31 (4.3) 19 (2.6) 6 16 (2.2)
698 18 13 145 104
Multipara n = 729
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No missing values for outcome variables unless stated. Percentages may not add up to 100 because of rounding. *n = 134, transferred births. Time between transfer and birth. †Maternal morbidity (supporting information) and birth related neonatal morbidity (supporting information) in the first week postpartum. NICU = neonatal intensive care unit; OASI = obstetric anal sphincter injury.
14 (1.9) 0 90 (12.3) 0 (0.0) 3 (1.6) 0 36 (18.8) 0 (0.0) 17 (1.8) 0 126 (13.7) 0 (0.0) 4 (1.7) 2 23 (9.5) 0 (0.0) 4 (6.3) 0 12 (18.8) 0 (0.0) 8 (2.6) 2 35 (11.4) 0 (0.0)
(0.0) (0.3) (9.1) (0.0) (0.1) (1.6) (11.1) (0.0) 1 20 136 0
25 (2.0) 2 161 (13.1) 0 (0.0)
(0.0) (1.2) (8.2) (0.0) 0 9 60 0 (0.5) (5.2) (25.0) (0.0) 1 10 48 0 (0.1) (2.1) (11.7) (0.0) 1 19 108 0 (0.0) (0.0) (6.2) (0.0) 0 0 15 0 0 1 13 0 0 1 28 0
(0.0) (1.6) (20.3) (0.0)
Primipara n = 64 n = 1,228
All n = 307
Cervical tear, n (%) Maternal blood transfusion, n (%) Maternal morbidity,† n (%) Maternal mortality, n (%) Neonatal Neonatal resuscitation, n (%) Missing Neonatal morbidity,† n (%) Neonatal mortality, n (%)
Table 2 (continued)
All
Planned Home
Multipara n = 243
All n = 921
Hospital
Primipara n = 192
Multipara n = 729
22
Oxytocin augmentation, epidural analgesia, and postpartum hemorrhage were interrelated, with a twentyfold OR for one intervention in the presence of the other (crude OR 20.27 [95% CI 14.30–28.74]). Both oxytocin augmentation and epidural analgesia were associated with significantly higher ORs for postpartum hemorrhage ≥ 500, ≥ 800, and ≥ 1,000 mL (crude ORs ranging from 2.25–3.73, 95% CIs ranging from 1.33 to 6.95). Subgroup analysis on the adjusted natural prospective approach, comparing each of the three hospital birth subgroups (obstetric unit group, n = 361; alongside midwifery unit group, n = 337; rural secondary hospital group, n = 223) to the home birth group, confirmed that oxytocin augmentation and postpartum hemorrhage ORs were significantly lower in the home birth group than all three hospital birth subgroups. Epidural analgesia ORs were also significantly lower in the home birth group compared with the obstetric unit and the rural secondary hospital, but differences between home births and the alongside midwifery unit were not significant (adjusted OR 0.89 [95% CI 0.50– 1.58]). Subgroup analysis on transfer for increased pain relief from home births and alongside midwifery unit births, which also needed transfer for this indication, revealed a significantly lower OR for home birth primiparas (adjusted OR 0.21 [95% CI 0.08–0.57]). Differences in other secondary outcome variables were not significant (Table 2). Sensitivity analysis on two separate models where confounders with high numbers of missing values were added (occupation model, n = 1,011; duration of labor model, n = 999) did not change the overall results of the study.
Discussion The study’s key findings were that the rates of oxytocin augmentation, epidural analgesia, and postpartum hemorrhage were significantly lower when labor started as a planned home birth. The study did not have power to detect significant differences in operative birth, OASI, NICU admission, or 5-minute Apgar score ˂ 7. Lower rates of oxytocin augmentation and epidural analgesia in the Icelandic home birth group were consistent with the outcomes of previous studies (3,4,6,7,9,10), while significant differences in the rates of operative births evident in other studies (3,4,6,8–11) were not apparent in Iceland. This lack of differences may be as a result of low study power, but may also be partially explained by population influences and the effect of midwifery services in labor. The operative birth rate in Iceland is the lowest in Europe (24) and accompanied by good birth outcomes, which indicates low rates of unnecessary operative births. If the low
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Table 3. Adjusted Odds Ratios for Birth Outcomes of Low-Risk Women Having Planned Home and Hospital Births in Iceland, 2005–2009
Planned Home Hospital OR—Reference
Natural prospective Birth Operative birth Oxytocin augmentation Epidural analgesia Maternal Postpartum hemorrhage ≥ 500 mL Postpartum hemorrhage ≥ 800 mL Postpartum hemorrhage ≥ 1,000 mL OASI Neonatal NICU admission 5-minute Apgar < 7
Perfect guideline Birth Operative birth Oxytocin augmentation Epidural analgesia Maternal Postpartum hemorrhage ≥ 500 mL Postpartum hemorrhage ≥ 800 mL Postpartum hemorrhage ≥ 1,000 mL OASI Neonatal NICU admission 5-minute Apgar < 7c
OR (95% CI)
OR (95% CI)
OR (95% CI)
All (n = 1,224)a
Primipara (n = 255)a
Multipara (n = 968)b
1.00 1.00 1.00
1.22 (0.63─2.36) 0.37 (0.23─0.59) 0.47 (0.29─0.74)
1.06 (0.41─2.76) 0.35 (0.17─0.71) 0.24 (0.11─0.51)
1.58 (0.49─5.09) 0.28 (0.14─0.58) 0.57 (0.30─1.09)
1.00 1.00 1.00 1.00
0.55 0.68 0.91 0.97
0.42 0.37 0.71 1.37
0.57 0.92 1.02 0.73
1.00 1.00
1.34 (0.78─2.32) 0.98 (0.30─3.19)
(0.36─0.85) (0.33─1.38) (0.41─2.05) (0.41─2.27)
(0.20─0.89) (0.10─1.36) (0.20─2.58) (0.40─4.63)
1.88 (0.81─4.36) 1.24 (0.25─6.28)
(0.33─1.00)d (0.37─2.28) (0.34─3.02) (0.20─2.59)
1.04 (0.46─2.34) 0.38 (0.04─3.60)
All (n = 1,108)a
Primiparaa (n = 227)
Multipara (n = 880)b
1.00 1.00 1.00
0.87 (0.40─1.89) 0.38 (0.23─0.63) 0.44 (0.27─0.74)
0.74 (0.26─2.14) 0.38 (0.18─0.80) 0.22 (0.10─0.50)
1.43 (0.34─5.96) 0.27 (0.12─0.58) 0.55 (0.27─1.11)
1.00 1.00 1.00 1.00
0.44 0.45 0.64 0.94
0.26 0.32 0.60 1.37
0.49 0.51 0.64 0.52
1.00 1.00
1.03 (0.55─1.94) 0.23 (0.03─1.92)
(0.27─0.71) (0.19─1.06) (0.24─1.67) (0.38─2.35)
(0.11─0.60) (0.08─1.30) (0.15─2.44) (0.40─4.72)
1.02 (0.37─2.80)
(0.27─0.90) (0.16─1.64) (0.16─2.54) (0.12─2.27)
1.09 (0.46─2.61) 0.44 (0.04─4.32)
a
Adjusted for maternal age, period of gestation, fetal presentation, water birth, smoking, birthweight, and gender. bAdjusted for maternal age, period of gestation, fetal presentation, water birth, smoking, birthweight, gender, previous births, and previous instrumental births. cAdjusted OR for primiparas not available, no home births with 5-minute Apgar < 7. dRounded up to 1.00. NICU = neonatal intensive care unit; OASI = obstetric anal sphincter injury.
operative birth rates in Iceland are indeed the result of a low rate of unnecessary operative births, there might not be any actual differences in the method of delivery between home and hospital births in the Icelandic population. Continuous one-to-one midwifery care in labor, routinely performed in all Icelandic birth settings, has been found to reduce operative birth rates when used alone or in combination with oxytocin augmentation, and may have contributed positively to Iceland’s low operative birth rates (28–30). On the other hand, oxytocin use by itself has not been proved to ameliorate the negative effect of epidural use on operative birth rates,
which is mediated by prolonged labor (31). Supportive care is a World Health Organization recommended intervention in essential childbirth care, but neither oxytocin augmentation nor epidural use is routinely recommended (32). In light of the association between those interventions and elevated risk of postpartum hemorrhage in hospital births, which was consistent with previous studies (2,3,9,10,13) and further reflected in substantial although nonsignificant differences in maternal blood transfusion rates, efforts should be made to examine the use of oxytocin augmentation and epidural analgesia in Icelandic hospital births. Low operative birth rates in home birth, in spite of signifi-
24 cantly less use of oxytocin and epidural, suggest that the oxytocin and epidural rates in the hospital setting might also be reduced without increasing the overall operative birth rates. Low oxytocin and epidural rates in the home birth group could be partially related to learned behaviors or pre-existing philosophies of the midwives who work in home birth, where those interventions are not available without transfer. If the reasons for the increased use of interventions in the hospitals mainly reside in technocratic institutional cultures (33), institutional changes could suffice to lower intervention rates, but the results of this study indicate that the intervention causality is more complex. Contrary to previous findings (5,7), the duration of the first stage of labor—difficult to adjust for as a result of high missing values—is significantly longer in planned hospital births in Iceland, clinically increasing the need for both oxytocin augmentation and epidural analgesia. If less functional labor in the hospital environment is causing higher intervention rates, reductions in interventions may be facilitated by substantial changes to the hospital birthing environment or increased access to home birth for low-risk women. This study does not add significant findings to the inconsistent knowledge on neonatal outcomes from previous studies. Considering the rarity of adverse neonatal outcomes in low-risk groups, Iceland’s low absolute number of births (23), and the country’s ranking the lowest in neonatal mortality rates in Europe (24), it is unlikely that statistical comparison of neonatal mortality and severe morbidity between service levels in Iceland will be feasible in the near future, even though the incidence of NICU admissions and mild to severe birth-related neonatal morbidity would justify auditing. In the foreseeable absence of conclusive evidence on neonatal outcome, policy on home birth in Iceland and other settings with small absolute home birth numbers might benefit from examining how the inconsistencies of previous studies reflect underlying differences in the structure of services and society. In the Netherlands, Canada, and New Zealand, where neonatal outcomes in home birth are similar to or better than hospital birth outcomes, home birth services are provided by certified midwives and are regulated and integrated into the health care system (6,9,10,18,19). Inconsistent results from the United States, ranging from mild benefits to elevated risk for serious neonatal morbidity in home birth, may reflect lack of regulation and integration within the health care system (12). The current home birth services in Iceland are provided by certified midwives with additional nursing education and are further strengthened by official guidelines on contraindications and transfer indications. Although insignificant and internally inconsistent (with neonatal resuscitation rates higher than the rates of low Apgar
BIRTH 42:1 March 2015
score, indicating an overuse of this intervention among multiparas in home and hospital birth), the increased rates of low Apgar scores and interventions for the neonates of home birth primiparas suggest that adding official guidelines on perinatal care, including guidelines on neonatal care (34), has the potential to increase home birth safety. Official rather than the current informal integration between home and hospital birth services could further increase consultation and transfer efficiency. Evidence-based guidelines for home birth need to be updated regularly to reflect best practice and current evidence, and would benefit from further studies on the effect of potential influential factors such as parity, contraindications, and quality of services. High transfer rates in Icelandic home birth are consistent with transfer rates in settings with high home birth rates like the United Kingdom and Canada (4,10), but warrant further inspection of transfer indication and effect. The issue of increased distance from place of birth to an obstetric institution, which appears to be related to negative maternal and neonatal outcomes in previous studies (35,36), would need to be studied in Iceland, which is a sparsely populated country with challenging terrain. Furthermore, the association between postpartum hemorrhage, oxytocin augmentation, and epidural analgesia in this study leaves room for the influence of women’s intervention preferences on postpartum hemorrhage rates, suggesting a need for studies on women’s attitudes toward home birth and interventions. Quantitative and qualitative studies on Icelandic families’ experiences and psycho-social outcomes after home and hospital birth would also add valuable information on home birth in Iceland. The present study had limited power to detect small differences in variables with low incidences, which may explain why differences in previous studies, such as reduced rates of perineal injury and other maternal morbidity indicators (2–6,8–11), were not detected. In spite of relatively high birth and home birth rates in Iceland, the country’s small absolute numbers of births (< 5,000 a year (23)) make it difficult to obtain large study groups. In the absence of randomization, a method which is not feasible in home birth studies (37), self-selection bias could not be avoided. The results of the study cannot therefore be directly generalized to other populations, but can nevertheless be indicative of home birth outcomes in many settings with a similar structure of service and society. The strength of the study was its ability to obtain the total national population of Icelandic home births, to exclude unplanned and unattended home births, and to include planned home births that ended in hospital after transfer. The study also had a rigorous process of data collection, matching, exclusion, and adjustment to increase reliability and validity. As a result of low
25
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absolute birth numbers in Iceland, not all home births with rare contraindications were successfully matched, resulting in a skewed hospital birth group with lower rates of contraindications. This skewness was addressed by using two separate approaches in the analysis, one of which excluded all contraindication cases and their matches. The two approaches in the analysis had similar trends and significance. Those working in childbirth services have an obligation to provide evidence-based services, guidelines, and information to women choosing their place of birth, and to respect that the choice is theirs. This study adds to the body of evidence suggesting that planned home birth for low-risk women is as safe as planned hospital birth, facilitating women’s informed choice. Further development of Icelandic home and hospital birth services and future studies on women’s attitudes and other influential factors such as parity, residence, and contraindications are recommended.
Acknowledgments This study was supported by grants from The Icelandic Research Fund for Graduate Students, the Memorial Fund for Midwife Bjorg Magnusdottir, and Farmer Magnus Jonasson and the Icelandic Midwives’ Association’s Research Fund. The authors thank Dr. Arna Hauksd ottir and pediatrician Þ orður Þ orkelsson for methodological assistance, Dr. Gunnar Stefansson and Sigr un Helga Lund for statistical assistance, and Neal O’Donoghue for proofreading. The results of the study were partially presented on June 2, 2014, at the International Confederation of Midwives 30th Triennial Congress in Prague (session C 016, presentation C 047).
References 1. Olsen O, Clausen JA. Planned hospital birth versus planned home birth. Cochrane Database Syst Rev 2012;9:Cd000352. 2. de Jonge A, Mesman JA, Manni€en J, et al. Severe adverse maternal outcomes among low risk women with planned home versus hospital births in the Netherlands: Nationwide cohort study. BMJ 2013;346:f3263. 3. Blix E, Huitfeldt AS, Øian P, et al. Outcomes of planned home births and planned hospital births in low-risk women in Norway between 1990 and 2007: A retrospective cohort study. Sex Reprod Healthc 2012;3(4):147–153. 4. Brocklehurst P, Hardy P, Hollowell J, et al. Perinatal and maternal outcomes by planned place of birth for healthy women with low risk pregnancies: The birthplace in England national prospective cohort study. BMJ 2011;343:d7400. 5. Chang JJ, Macones GA. Birth outcomes of planned home births in Missouri: A population-based study. Am J Perinatol 2011;28 (7):529–536.
6. Davis D, Baddock S, Pairman S, et al. Planned place of birth in New Zealand: Does it affect mode of birth and intervention rates among low-risk women? Birth 2011;38(2):111–119. 7. Wax JR, Pinette MG, Cartin A, Blackstone J. Maternal and newborn morbidity by birth facility among selected United States 2006 low-risk births. Am J Obstet Gynecol 2010;202(2):152.e1–5. 8. Kennare RM, Keirse MJ, Tucker GR, Chan AC. Planned home and hospital births in South Australia, 1991-2006: Differences in outcomes. Med J Aust 2010;192(2):76–80. 9. Janssen PA, Saxell L, Page LA, et al. Outcomes of planned home birth with registered midwife versus planned hospital birth with midwife or physician. CMAJ 2009;181(6–7):377–383. 10. Hutton EK, Reitsma AH, Kaufman K. Outcomes associated with planned home and planned hospital births in low-risk women attended by midwives in Ontario, Canada, 2003-2006: A retrospective cohort study. Birth 2009;36(3):180–189. 11. Lindgren HE, Radestad IJ, Christensson K, Hildingsson IM. Outcome of planned home births compared to hospital births in Sweden between 1992 and 2004. A population-based register study. Acta Obstet Gynecol Scand 2008;87(7):751–759. 12. Cheng YW, Snowden JM, King TL, Caughey AB. Selected perinatal outcomes associated with planned home births in the United States. Am J Obstet Gynecol 2013;209(4):325.e321-328. 13. Nove A, Berrington A, Matthews Z. Comparing the odds of postpartum haemorrhage in planned home birth against planned hospital birth: Results of an observational study of over 500,000 maternities in the UK. BMC Pregnancy Childbirth 2012;12 (1):130. 14. Davis D, Baddock S, Pairman S, et al. Risk of severe postpartum haemorrhage in low-risk childbearing women in New Zealand: Exploring the effect of place of birth and comparing third stage management of labour. Birth 2012;39(2):98–105. 15. Malloy MH. Infant outcomes of certified nurse midwife attended home births: United States 2000 to 2004. J Perinatol 2010;30 (9):622–627. 16. Grunebaum A, McCullough LB, Sapra KJ, et al. Apgar score of 0 at 5 minutes and neonatal seizures or serious neurologic dysfunction in relation to birth setting. Am J Obstet Gynecol 2013;209(4):323.e321-326. 17. Grunebaum A, McCullough LB, Sapra KJ, et al. Early and total neonatal mortality in relation to birth setting in the United States, 2006–2009. Am J Obstet Gynecol. 2014;211(4):390.e1–7. 18. van der Kooy J, Poeran J, de Graaf JP, et al. Planned home compared with planned hospital births in the Netherlands: Intrapartum and early neonatal death in low-risk pregnancies. Obstet Gynecol 2011;118(5):1037–1046. 19. de Jonge A, van der Goes BY, Ravelli AC, et al. Perinatal mortality and morbidity in a nationwide cohort of 529,688 low-risk planned home and hospital births. BJOG 2009;116(9):1177– 1184. 20. Chervenak FA, McCullough LB, Arabin B. Obstetric ethics: An essential dimension of planned home birth. Obstet Gynecol 2011;117(5):1183–1187. 21. Symon A, Winter C, Donnan PT, Kirkham M. Examining autonomy’s boundaries: A follow-up review of perinatal mortality cases in UK independent midwifery. Birth 2010;37(4):280–287. 22. Embaetti landlaeknis. Hlutfall heimafaedinga af ollum faedingum a Islandi 1980-2010 [Home Birth Rates in Iceland 1980-2010] [Internet]. Reykjavik: Embaetti Landlaeknis; 2012. Icelandic. Accessed November 25, 2014. Available at: http://www.landlaeknir.is/servlet/file/store93/item4245/version8/fileservice66/4245_66_ preview.pdf. 23. Bjarnadottir RI. Yfirlit yfir faedingar arid 2012 [A Summary of Births in 2012]. In: Bjarnadottir RI, Gardarsdottir G, Smarason AK, Palsson GI, eds. Skyrsla fra Faedingaskraningunni Fyrir
BIRTH 42:1 March 2015
26
24.
25.
26.
27.
28.
29.
30.
31.
32.
Arid 2012 [Birth Registry Rapport for the Year 2012]. Reykjavik: Landspitali, Kvenna- og barnasvid, 2013:4–7. Icelandic. EURO-PERISTAT Project with SCPE and EUROCAT. European Perinatal Health Report. The health and care of pregnant women and babies in Europe in 2010. Paris: EURO-PERISTAT Project; 2013. Accessed November 25, 2014. Available at: www. europeristat.com. Lindgren H, Kjaergaard H, Olafsdottir OA, Blix E. Praxis and guidelines for planned homebirths in the Nordic countries - an overview. Sex Reprod Healthc 2014;5(1):3–8. Landlaeknisembaettid. Leidbeiningar um val a faedingarstad [Guidelines for Choice in Place of Birth]. Reykjavik: Landlaeknisembaettid; 2007. Icelandic. Halfdansdottir B [Giving birth at home – risk or reward? Comparing the outome of planned home and hospital birth in Iceland 2005-2009: A retrospective case-control pilot study]. Ljosmaedrabladid 2011;89(2):6–12. Icelandic. Brown HC, Paranjothy S, Dowswell T, Thomas J. Package of care for active management in labour for reducing caesarean section rates in low-risk women. Cochrane Database Syst Rev 2013;9:Cd004907. Hodnett ED, Gates S, Hofmeyr GJ, Sakala C. Continuous support for women during childbirth. Cochrane Database Syst Rev 2013;7:Cd003766. Wei S, Wo BL, Qi HP, et al. Early amniotomy and early oxytocin for prevention of, or therapy for, delay in first stage spontaneous labour compared with routine care. Cochrane Database Syst Rev 2013;8:Cd006794. Costley PL, East CE. Oxytocin augmentation of labour in women with epidural analgesia for reducing operative deliveries. Cochrane Database Syst Rev 2013;7:Cd009241. World Health Organization. WHO Recommended Interventions for Improving Maternal and Newborn Health: Integrated management of pregnancy and childbirth [Internet]. 2nd ed. Geneva: WHO
33.
34. 35.
36.
37.
Press; 2009. Accessed November 25, 2014. Available at: http:// whqlibdoc.who.int/hq/2007/WHO_MPS_07.05_eng.pdf?ua=1. Davis-Floyd R. The technocratic, humanistic, and holistic paradigms of childbirth. Int J Gynaecol Obstet 2001;75(Suppl 1):S5– S23. Committee on Fetus and Newborn. Planned home birth. Pediatrics 2013;131(5):1016. Engjom H, Morken NH, Norheim O, Klungsoyr K. Availability and access in modern obstetric care: A retrospective populationbased study. BJOG 2014;121(3):290–299. Ravelli AC, Jager KJ, de Groot MH, et al. Travel time from home to hospital and adverse perinatal outcomes in women at term in the Netherlands. BJOG 2011;118(4):457–465. Hendrix M, Van Horck M, Moreta D, et al. Why women do not accept randomisation for place of birth: Feasibility of a RCT in the Netherlands. BJOG 2009;116(4):537–542; discussion 542– 534.
Supporting Information Additional Supporting Information may be found in the online version of this article: Appendix 1. Contraindications for Home Births and Hospital Births Matching Low-Risk Home Births. Appendix 2. ICD-10 Diagnoses Categorized as Maternal Morbidity in the First Week Postpartum. Appendix 3. ICD-10 Diagnoses Categorized as Birth Related Neonatal Morbidity in the First Week Postpartum.
16
Outcome of Planned Home and Hospital Births among Low-Risk Women in Iceland in 2005–2009: A Retrospective Cohort Study Berglind Halfdansdottir, RN, RM, MSc, Alexander Kr. Smarason, MD, DPhil, FRCOG, Olof A. Olafsdottir, RN, RM, MSc, PhD, Ingegerd Hildingsson, RN, RM, MSc, PhD, and Herdis Sveinsdottir, RN, MSc, PhD ABSTRACT: Background: At 2.2 percent in 2012, the home birth rate in Iceland is the highest in the Nordic countries and has been rising rapidly in the new millennium. The objective of this study was to compare the outcomes of planned home births and planned hospital births in comparable low-risk groups in Iceland. Methods: The study is a retrospective cohort study comparing the total population of 307 planned home births in Iceland in 2005–2009 to a matched 1:3 sample of 921 planned hospital births. Regression analysis, adjusted for confounding variables, was performed for the primary outcome variables. Results: The rate of oxytocin augmentation, epidural analgesia, and postpartum hemorrhage was significantly lower when labor started as a planned home birth. Differences in the rates of other primary outcome variables were not significant. The home birth group had lower rates of operative birth and obstetric anal sphincter injury. The rate of 5-minute Apgar score < 7 was the same in the home and hospital birth groups, but the home birth group had a higher rate of neonatal intensive care unit admission. Intervention and adverse outcome rates in both study groups, including transfer rates, were higher among primiparas than multiparas. Oxytocin augmentation, epidural analgesia, and postpartum hemorrhage rates were significantly interrelated. Conclusions: This study adds to the growing body of evidence that suggests that planned home birth for low-risk women is as safe as planned hospital birth. (BIRTH 42:1 March 2015)
Key words: midwifery, outcome, planned home birth, planned hospital birth
Observational studies on the outcome of home birth in Western societies have become more frequent in recent years and of greater methodological quality (1), increasing the scientific knowledge on the safety of home birth. Studies from different countries such as the United States, Canada, the United Kingdom, the Netherlands, Norway, Sweden, Australia, and New Zealand
indicate that maternal outcome is equally good or better in home birth than in hospital birth settings, with significantly less intervention (2–12) and morbidity (2,3,5,6,8–11,13,14), except for more frequent prolonged labor (5,7). Results on neonatal outcomes in home birth are less consistent: Some studies, predominantly from the United States, indicate that severe
Berglind Halfdansdottir is a Doctoral Student of Midwifery at Faculty of Nursing, School of Health Sciences, University of Iceland, Reykjavik, Iceland; Alexander Kr. Smarason is a Professor at School of Health Sciences, University of Akureyri, Akureyri, Iceland; Olof A. Olafsdottir is an Assistant Professor of Midwifery at Faculty of Nursing, School of Health Sciences, University of Iceland, Reykjavik, Iceland; Ingegerd Hildingsson is a Professor of Nursing Sciences at Department of Nursing, Mid Sweden University, Sundsvall, Sweden; Herdis Sveinsdottir is a Professor of Nursing at Faculty of Nursing, School of Health Sciences, University of Iceland, Reykjavik, Iceland.
Address correspondence to Berglind Halfdansdottir, RN, RM, MSc, Faculty of Nursing, School of Health Sciences, University of Iceland, Reykjavik, Eirbergi, Eirıksg€otu 34, Iceland.
Accepted November 25, 2014
© 2015 Wiley Periodicals, Inc.
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neonatal morbidity and mortality are significantly more likely in home than in hospital births (4,5,7,8,12,15– 17), while other studies from the United States, Canada, the Netherlands, Australia, and New Zealand describe either similar or better outcomes on neonatal morbidity, mortality, or need for medical assistance (6– 10,12,15,18,19). Information on the outcome of childbirth services is an essential part of a childbearing woman’s autonomy. Respect for a woman’s right to informed choice in place of birth is mirrored in health professionals’ duty to provide information applicable to the woman’s situation (20,21). Differences in home birth outcome may reflect underlying differences in the way home birth services are organized and regulated. When the results of previous studies are not generalizable to a given population, localized studies are important to maintain informed choice. The home birth rate in Iceland is the highest among the Nordic countries. Following a historical low of 0.1 percent in the 1990s (22), the rate has been rising rapidly in the new millennium, reaching 2.2 percent in 2012 (23). This study is the first to examine the outcome of home births in Iceland. Its purpose is to facilitate women’s informed choice in place of birth, to support further development of childbirth services, and to add to the growing body of international knowledge on home birth in the context of setting. The aim of the study is to answer two research questions: What is the outcome of planned home births in Iceland; and are there significant differences between the outcomes of planned home births and planned hospital births in comparable low-risk groups in that country?
Methods This study is a retrospective cohort study on the relationship between an independent variable—place of birth—and various dependent outcome variables. The study was approved by six regional health care authorities, 22 independent midwives, the Icelandic Data Protection Authority (no. PV2010/381), and the National Bioethics Committee (no. 10-064-S1). The study setting was in Iceland, a country with harsh terrain and unpredictable weather, a population of 325,000 and a low population density, conditions which can result in difficult long-distance traveling before or during labor. At 2.20 in 2010, Iceland’s fertility rate is the highest in Europe, and its home birth rate is the third highest for the same region, ranking only behind the Netherlands and the United Kingdom (24). In the capital area of Reykjavik, where 64 percent of the total population resides and where the country’s only tertiary hospital is located, 75 percent of home and hospital
births in Iceland take place (23). During the time of the study (2005–2009), the tertiary hospital was furnished with two birthing units, a high-risk obstetric unit and a low-risk alongside midwifery unit. In rural areas during the same period, one secondary and four primary hospitals offered services to low-, medium-, or high-risk women, in addition to the services of four low-risk units and home birth services (23,25). Home and hospital births in Iceland are attended to by midwives who obtain a license to practice after a 4year bachelor’s of science course in nursing and an additional 2-year master-level course in midwifery. The independent practices of home birth midwives are publicly funded (25) and are regulated and supervised by the Icelandic Directorate of Health, which has issued national guidelines for choice in place of birth. Contraindications for home birth and indications for intrapartum transfer are listed in the guidelines (25,26). An Icelandic electronic birth registry, commissioned and supervised by the Directorate of Health, is lacking data that would enable researchers to differentiate between planned and unplanned home births, or identify planned home births that end in hospital after transfer (25). It also lacks important outcome variables and confounders, such as the amount or severity of bleeding after birth, body mass index, and smoking. The information for the study’s database was therefore collected directly by the first author from the midwives’ and doctors’ original hand-written maternity notes, stored in various urban and rural locations. A structured item list of predefined variables and their values was used to ensure data collection completeness and homogeneity. For comparative purposes, the list was partially based on an item list used in a Norwegian study on home birth (3). The structured item list was translated and localized and the variables conceptualized and operationalized in an Icelandic pilot study (27). Data from the electronic birth registry were used for three planned home births for which all or some maternity notes were missing. Iceland’s small absolute numbers of births and midwives made it possible to contact every practicing home birth midwife directly. Thus, the total population of 307 planned home births accepted for midwifery care in Iceland at the onset of labor in 2005–2009 were included in this study, regardless of eventual place of birth (i.e., home births ending in hospital after transfer were included, while unplanned and unattended home births were excluded). The control group consisted of a purposive sample of 921 hospital births planned in the tertiary hospital (obstetric or alongside midwifery unit) or the rural secondary hospital. The control group was matched on parity (primipara vs multipara); contraindications (if present in the home birth); residence (capital vs rural, by transfer
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18 time to hospital); maternal age ( 2 years); and year of birth (next in chronological order) in a 1:3 ratio, resulting in a total n = 1,228. Controls with any of 67 predefined contraindications (supporting information), based on the Directorate of Health’s guidelines for home births, were excluded when matching low-risk home births without contraindications. Home births that were planned in spite of such contraindications were matched with controls with the same contraindications when possible; otherwise, they were matched with controls with no contraindications. The independent variable of the study—planned place of birth at the onset of labor—divided the study group into the home birth group and the hospital birth group. The primary dependent outcome variables were operative birth (instrumental or cesarean), oxytocin augmentation, epidural analgesia, bleeding after birth (continuous variable), and postpartum hemorrhage (three dichotomous categorical variables: ≥ 500, ≥ 800, and ≥ 1,000 mL), obstetric anal sphincter injury (OASI), neonatal intensive care unit (NICU) admission, and 5-minute Apgar scores < 7. Characteristics of participants and secondary dependent outcome variables are listed in Tables 1 and 2, respectively. Characteristics of participants were analyzed using t tests for continuous variables, Fisher exact test for the presence of a midwife, and chi-squared for other categorical variables (Table 1). Linear regression analysis for continuous primary outcome variables and logistic regression analysis for categorical primary outcome variables was performed on SPSS 21 (Table 3). Backwards selection of potential confounders was performed by testing models for six outcome variables with relatively high incidence. The regression model included nine confounders that significantly improved the model (maternal age; period of gestation; fetal presentation; water birth; smoking; birthweight; gender; parity; previous instrumental births). Sensitivity analysis was performed by running two separate models, adding confounders with high numbers of missing values (occupation; duration of labor). The study had two main approaches: 1) the natural prospective approach (intention to treat), including all home births and all matching hospital births, some with known contraindications; and 2) the perfect guideline approach (per protocol), including only low-risk home births and their matches. The approaches were further stratified by parity.
Results The natural prospective approach included 1,228 births. For the perfect guideline approach, 29 home births that were planned in spite of contraindications
and their 87 matches were excluded, leaving 1,112 births. Characteristics of participants in relation to place of birth are described in Table 1. Women planning home birth were significantly more likely to be married with a high occupational status. Home birth multiparas were significantly more likely to have had a previous home birth and they had a higher mean number of previous births. Home births had a significantly shorter first stage of labor, but a longer third stage and gestation period. They were significantly more likely to be water births and less likely to have a midwife present at the birth of the baby (as a result of precipitous labor); midwives were present at 98.4 percent of home births, and all hospital births. Home birth neonates were significantly less likely to have congenital anomalies, ranging from mild to severe. The study had no incidences of maternal or neonatal mortality (Table 2). The home birth group had lower rates of operative birth (both instrumental and cesarean), oxytocin augmentation, and epidural analgesia, compared with the hospital birth group. Women in the home birth group had lower rates of postpartum hemorrhage, OASI, episiotomy, cervical tear, blood transfusion, and morbidity in the first week postpartum, but a higher rate of vaginal tears, compared with women in the hospital birth group. Neonates in the home birth group had the same rates of 5-minute Apgar score < 7 as neonates in the hospital birth group. Neonates in the home birth group had higher rates of NICU admission and neonatal resuscitation, but lower rates of morbidity in the first week postpartum. Intervention and adverse outcome rates in both study groups were higher among primiparas than multiparas (Table 2). Transfer rates were also higher among primiparas than multiparas, but were not clinically comparable between the study groups because the indications for transfer were not the same in home and hospital births (26). Logistic regression on oxytocin augmentation, epidural analgesia, and postpartum hemorrhage as a categorical variable (≥ 500 mL [crude and adjusted] and ≥ 800 mL [crude]) revealed significantly lower odds ratios (ORs) in home births than in hospital births (Table 3), indicating that these interventions and adverse outcomes were significantly less frequent in the home birth group. Linear regression on bleeding after birth as a continuous variable also predicted significantly reduced bleeding in home birth, with differences between home and hospital birth ranging from 77 to 114 mL between models. The study lacked sufficient power (p = 1 b = 0.8) to detect differences in primary outcome variables with low incidences, such as operative birth (instrumental or cesarean), postpartum hemorrhage ≥ 1,000 mL, OASI, NICU admission, and 5-minute Apgar score < 7.
19
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Table 1. Characteristics of Low-Risk Women Having Planned Home and Hospital Births in Iceland, 2005–2009
Demographic Age, mean SD/n (%) < 25 25–34 ≥ 35 Year of birth, n (%) 2005 2006 2007 2008 2009 Residence, n (%) Capital (all ≤ 20 min) Rural ≤ 20 min Rural ˃ 20 ≤ 60 min Rural ˃ 60 min Marital status, n (%) Married Cohabiting Single Missing Occupation,* n (%) Specialist Semispecialist Nonspecialist Missing Citizenship, n (%) Icelandic Non-Icelandic Missing Clinical Parity, mean SD/n (%) Primipara Multipara Previous home births, n (%) No Yes Missing Previous instrumental births, n (%) No Yes Missing Body mass index, mean SD/n (%) < 25 25–29.99
All n = 1,228
Planned Home n = 307
Hospital n = 921
30.3 4.7 136 (11.1) 857 (69.8) 235 (19.1)
30.6 4.9 33 (10.7) 202 (65.8) 72 (23.5)
30.2 4.7 103 (11.2) 655 (71.1) 163 (17.7)
p 0.120
0.084
150 170 253 276 379
(12.2) (13.8) (20.6) (22.5) (30.9)
41 42 62 67 95
(13.4) (13.7) (20.2) (21.8) (30.9)
109 128 191 209 284
(11.8) (13.9) (20.7) (22.7) (30.8)
0.968
931 196 56 45
(75.8) (16.0) (4.6) (3.7)
232 50 14 11
(75.6) (16.3) (4.6) (3.6)
699 146 42 34
(75.9) (15.9) (4.6) (3.7)
0.998
505 (41.2) 650 (53.0) 72 (5.9) 1
143 (46.6) 156 (50.8) 8 (2.6) 0
362 (39.3) 494 (53.7) 64 (7.0) 1
569 (56.1) 304 (30.0) 142 (14.0) 213
170 (59.4) 89 (31.1) 27 (9.4) 21
399 (54.7) 215 (29.5) 115 (15.8) 192
1,085 (91.2) 105 (8.8) 38
286 (93.8) 19 (6.2) 2
799 (90.3) 86 (9.7) 36
1.24 0.93 256 (20.8) 972 (79.2)
1.40 1.08 64 (20.8) 243 (79.2)
1.18 0.87 192 (20.8) 729 (79.2)
1,155 (94.3) 70 (5.7) 3
235 (77.0) 70 (23.0) 2
1,088 (88.8) 137 (11.2) 3 25.0 4.3 676 (56.9) 356 (30.0)
275 (90.2) 30 (9.8) 2 24.8 4.1 171 (59.2) 88 (30.4)
920 (100.0) 0 (0.0) 1 813 (88.4) 107 (11.6) 1 25.1 4.4 505 (56.2) 268 (29.8)
0.005
0.032
0.064 0.002 1.000
< 0.001
0.389 0.291
(continued)
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20 Table 1 (continued)
All n = 1,228 ≥ 30 Missing Smoking, n (%) No Little Missing Mental health problems, n (%) No Yes Contraindications,† n (%) No Yes Birth-related Gestation, days (mean SD) Birthweight, g (mean SD) SGA, n (%) No Yes Congenital anomalies, n (%) No Yes Gender, n (%) Girl Boy Duration of labor (mean SD) Stage 1 Stage 2 Stage 3 Missing‡ Midwife present, n (%) No Yes Fetal presentation, n (%) Occupito-Anterior Occupito-Posterior Other Water birth, n (%) No Yes
Planned Home n = 307
Hospital n = 921
p
156 (13.1) 40
30 (10.4) 18
126 (14.0) 22
0.276
1,189 (97.1) 35 (2.9) 4
294 (97.0) 9 (3.0) 4
895 (97.2) 26 (2.8) 0
1,175 (95.7) 53 (4.3)
290 (94.5) 17 (5.5)
885 (96.1) 36 (3.9)
0.224
1,129 (91.9) 99 (8.1)
278 (90.6) 29 (9.4)
851 (92.4) 70 (7.6)
0.304
281.4 7.4 3,764 475
282.4 7.6 3,788 500
281.1 7.3 3,757 466
0.008 0.322
1,186 (96.6) 42 (3.4)
297 (96.7) 10 (3.3)
889 (96.5) 32 (3.5)
0.856
1,171 (95.4) 57 (4.6)
300 (97.7) 7 (2.3)
871 (94.6) 50 (5.4)
0.023
622 (50.7) 606 (49.3) 08:00 5:01 07:19 4:53 00:31 0:34 00:12 0:13 228
162 (52.8) 145 (47.2) 07:29 5:02 06:48 4:52 00:30 0:39 00:17 0:19 45
460 (49.9) 461 (50.1) 08:11 4:59 07:30 4:53 00:32 0:32 00:10 0:10 183
5 (0.4) 1,223 (99.6)
5 (1.6) 302 (98.4)
0 (0.0) 921 (100.0)
0.001
1,120 (91.2) 76 (6.2) 32 (2.6)
284 (92.5) 16 (5.2) 7 (2.3)
836 (90.8) 60 (6.5) 25 (2.7)
0.646
1,046 (85.2) 182 (14.8)
187 (60.9) 120 (39.1)
859 (93.3) 62 (6.7)
< 0.001
0.894
0.392 0.055 0.047 0.348 < 0.001
Percentages may not add up to 100 because of rounding. *Categorized using the Statistic Iceland‘s ISTARF95 classification system (based on the ISCO-88 International Standard Classification of Occupations). Variable values are proxies for Icelandic primary, secondary, and university education. †Predefined contraindications (supporting information) present in the study population: Hypertensive disorders; previous cesarean delivery; isoimmunization; prolonged pregnancy; hyperthyroidism; bipolar affective disorder; abnormal findings on antenatal screening; macrosomia or anticipated maternal–fetal disproportion; Body Mass Index > 35 or < 18. ‡Missing for any stage. Mean duration of stages does not add up to mean duration of labor because of differences in missing values. SGA = small for gestational age.
Primary outcomes Birth Method of delivery, n (%) Spontaneous vaginal birth Instrumental birth Cesarean birth Oxytocin augmentation, n (%) Epidural analgesia, n (%) Maternal Bleeding after birth (mL) (mean SD) Postpartum hemorrhage ≥ 500 mL n (%) Postpartum hemorrhage ≥ 800 mL n (%) Postpartum hemorrhage ≥ 1,000 mL n (%) Missing OASI, n (%) Neonatal NICU admission, n (%) 5-minute Apgar < 7, n (%) Secondary outcomes Birth Transfers, n (%) Transfer indication, n (%) Increased pain relief needed Prolonged labor, stimulation needed Other Urgent transfers, n (%) Transfer timing* (mean SD) Maternal Episiotomy, n (%) Vaginal tear, n (%) 66 (5.4) 17 (1.4)
14 (4.6) 6 (2.0)
(3.6) (6.5) (7.8) (0.0) 3:55
(10.9) (15.6) (12.5) (0.0) 4:06 9 (14.1) 2 (3.1)
7 10 8 0 6:19
25 (39.1)
55 (17.9) 11 20 24 0 4:55
12 (18.8) 4 (6.3)
(81.3) (10.9) (7.8) (26.6) (21.9)
400 307 16 (25.0) 4 (6.3) 4 (6.3) 0 4 (6.3)
52 7 5 17 14
22 (7.2) 5 (1.6)
(93.8) (3.9) (2.3) (8.8) (8.5)
85 (6.9) 20 (1.6)
288 12 7 27 26
Primipara n = 64
288 240 39 (12.9) 11 (3.6) 9 (3.0) 5 8 (2.6)
(92.8) (4.4) (2.8) (22.0) (18.6)
All n = 307
Planned Home
349 259 214 (17.6) 64 (5.3) 43 (3.5) 13 36 (2.9)
1,140 54 34 270 228
n = 1,228
All
(97.1) (2.1) (0.8) (4.1) (4.9)
(1.6) (4.1) (6.6) (0.0) 3:24 5 (2.1) 4 (1.6)
4 10 16 0 3:45
30 (12.3)
10 (4.1) 1 (0.4)
258 209 23 (9.7) 7 (2.9) 5 (2.1) 5 4 (1.6)
236 5 2 10 12
Multipara n = 243
Table 2. Birth Outcomes of Low-Risk Women Having Planned Home and Hospital Births in Iceland, 2005–2009
(92.5) (4.6) (2.9) (26.4) (21.9)
52 (5.6) 11 (1.2)
63 (6.8) 15 (1.6)
369 262 175 (19.2) 53 (5.8) 34 (3.7) 8 28 (3.0)
852 42 27 243 202
All n = 921
(80.2) (12.5) (7.3) (51.0) (51.0)
27 (14.1) 8 (4.2)
23 (12.0) 6 (3.1)
455 317 67 (35.3) 22 (11.6) 15 (7.9) 2 12 (6.3)
154 24 14 98 98
Primipara n = 192
Hospital
(95.7) (2.5) (1.8) (19.9) (14.3)
(continued)
25 (3.4) 3 (0.4)
40 (5.5) 9 (1.2)
346 240 108 (14.9) 31 (4.3) 19 (2.6) 6 16 (2.2)
698 18 13 145 104
Multipara n = 729
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21
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No missing values for outcome variables unless stated. Percentages may not add up to 100 because of rounding. *n = 134, transferred births. Time between transfer and birth. †Maternal morbidity (supporting information) and birth related neonatal morbidity (supporting information) in the first week postpartum. NICU = neonatal intensive care unit; OASI = obstetric anal sphincter injury.
14 (1.9) 0 90 (12.3) 0 (0.0) 3 (1.6) 0 36 (18.8) 0 (0.0) 17 (1.8) 0 126 (13.7) 0 (0.0) 4 (1.7) 2 23 (9.5) 0 (0.0) 4 (6.3) 0 12 (18.8) 0 (0.0) 8 (2.6) 2 35 (11.4) 0 (0.0)
(0.0) (0.3) (9.1) (0.0) (0.1) (1.6) (11.1) (0.0) 1 20 136 0
25 (2.0) 2 161 (13.1) 0 (0.0)
(0.0) (1.2) (8.2) (0.0) 0 9 60 0 (0.5) (5.2) (25.0) (0.0) 1 10 48 0 (0.1) (2.1) (11.7) (0.0) 1 19 108 0 (0.0) (0.0) (6.2) (0.0) 0 0 15 0 0 1 13 0 0 1 28 0
(0.0) (1.6) (20.3) (0.0)
Primipara n = 64 n = 1,228
All n = 307
Cervical tear, n (%) Maternal blood transfusion, n (%) Maternal morbidity,† n (%) Maternal mortality, n (%) Neonatal Neonatal resuscitation, n (%) Missing Neonatal morbidity,† n (%) Neonatal mortality, n (%)
Table 2 (continued)
All
Planned Home
Multipara n = 243
All n = 921
Hospital
Primipara n = 192
Multipara n = 729
22
Oxytocin augmentation, epidural analgesia, and postpartum hemorrhage were interrelated, with a twentyfold OR for one intervention in the presence of the other (crude OR 20.27 [95% CI 14.30–28.74]). Both oxytocin augmentation and epidural analgesia were associated with significantly higher ORs for postpartum hemorrhage ≥ 500, ≥ 800, and ≥ 1,000 mL (crude ORs ranging from 2.25–3.73, 95% CIs ranging from 1.33 to 6.95). Subgroup analysis on the adjusted natural prospective approach, comparing each of the three hospital birth subgroups (obstetric unit group, n = 361; alongside midwifery unit group, n = 337; rural secondary hospital group, n = 223) to the home birth group, confirmed that oxytocin augmentation and postpartum hemorrhage ORs were significantly lower in the home birth group than all three hospital birth subgroups. Epidural analgesia ORs were also significantly lower in the home birth group compared with the obstetric unit and the rural secondary hospital, but differences between home births and the alongside midwifery unit were not significant (adjusted OR 0.89 [95% CI 0.50– 1.58]). Subgroup analysis on transfer for increased pain relief from home births and alongside midwifery unit births, which also needed transfer for this indication, revealed a significantly lower OR for home birth primiparas (adjusted OR 0.21 [95% CI 0.08–0.57]). Differences in other secondary outcome variables were not significant (Table 2). Sensitivity analysis on two separate models where confounders with high numbers of missing values were added (occupation model, n = 1,011; duration of labor model, n = 999) did not change the overall results of the study.
Discussion The study’s key findings were that the rates of oxytocin augmentation, epidural analgesia, and postpartum hemorrhage were significantly lower when labor started as a planned home birth. The study did not have power to detect significant differences in operative birth, OASI, NICU admission, or 5-minute Apgar score ˂ 7. Lower rates of oxytocin augmentation and epidural analgesia in the Icelandic home birth group were consistent with the outcomes of previous studies (3,4,6,7,9,10), while significant differences in the rates of operative births evident in other studies (3,4,6,8–11) were not apparent in Iceland. This lack of differences may be as a result of low study power, but may also be partially explained by population influences and the effect of midwifery services in labor. The operative birth rate in Iceland is the lowest in Europe (24) and accompanied by good birth outcomes, which indicates low rates of unnecessary operative births. If the low
23
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Table 3. Adjusted Odds Ratios for Birth Outcomes of Low-Risk Women Having Planned Home and Hospital Births in Iceland, 2005–2009
Planned Home Hospital OR—Reference
Natural prospective Birth Operative birth Oxytocin augmentation Epidural analgesia Maternal Postpartum hemorrhage ≥ 500 mL Postpartum hemorrhage ≥ 800 mL Postpartum hemorrhage ≥ 1,000 mL OASI Neonatal NICU admission 5-minute Apgar < 7
Perfect guideline Birth Operative birth Oxytocin augmentation Epidural analgesia Maternal Postpartum hemorrhage ≥ 500 mL Postpartum hemorrhage ≥ 800 mL Postpartum hemorrhage ≥ 1,000 mL OASI Neonatal NICU admission 5-minute Apgar < 7c
OR (95% CI)
OR (95% CI)
OR (95% CI)
All (n = 1,224)a
Primipara (n = 255)a
Multipara (n = 968)b
1.00 1.00 1.00
1.22 (0.63─2.36) 0.37 (0.23─0.59) 0.47 (0.29─0.74)
1.06 (0.41─2.76) 0.35 (0.17─0.71) 0.24 (0.11─0.51)
1.58 (0.49─5.09) 0.28 (0.14─0.58) 0.57 (0.30─1.09)
1.00 1.00 1.00 1.00
0.55 0.68 0.91 0.97
0.42 0.37 0.71 1.37
0.57 0.92 1.02 0.73
1.00 1.00
1.34 (0.78─2.32) 0.98 (0.30─3.19)
(0.36─0.85) (0.33─1.38) (0.41─2.05) (0.41─2.27)
(0.20─0.89) (0.10─1.36) (0.20─2.58) (0.40─4.63)
1.88 (0.81─4.36) 1.24 (0.25─6.28)
(0.33─1.00)d (0.37─2.28) (0.34─3.02) (0.20─2.59)
1.04 (0.46─2.34) 0.38 (0.04─3.60)
All (n = 1,108)a
Primiparaa (n = 227)
Multipara (n = 880)b
1.00 1.00 1.00
0.87 (0.40─1.89) 0.38 (0.23─0.63) 0.44 (0.27─0.74)
0.74 (0.26─2.14) 0.38 (0.18─0.80) 0.22 (0.10─0.50)
1.43 (0.34─5.96) 0.27 (0.12─0.58) 0.55 (0.27─1.11)
1.00 1.00 1.00 1.00
0.44 0.45 0.64 0.94
0.26 0.32 0.60 1.37
0.49 0.51 0.64 0.52
1.00 1.00
1.03 (0.55─1.94) 0.23 (0.03─1.92)
(0.27─0.71) (0.19─1.06) (0.24─1.67) (0.38─2.35)
(0.11─0.60) (0.08─1.30) (0.15─2.44) (0.40─4.72)
1.02 (0.37─2.80)
(0.27─0.90) (0.16─1.64) (0.16─2.54) (0.12─2.27)
1.09 (0.46─2.61) 0.44 (0.04─4.32)
a
Adjusted for maternal age, period of gestation, fetal presentation, water birth, smoking, birthweight, and gender. bAdjusted for maternal age, period of gestation, fetal presentation, water birth, smoking, birthweight, gender, previous births, and previous instrumental births. cAdjusted OR for primiparas not available, no home births with 5-minute Apgar < 7. dRounded up to 1.00. NICU = neonatal intensive care unit; OASI = obstetric anal sphincter injury.
operative birth rates in Iceland are indeed the result of a low rate of unnecessary operative births, there might not be any actual differences in the method of delivery between home and hospital births in the Icelandic population. Continuous one-to-one midwifery care in labor, routinely performed in all Icelandic birth settings, has been found to reduce operative birth rates when used alone or in combination with oxytocin augmentation, and may have contributed positively to Iceland’s low operative birth rates (28–30). On the other hand, oxytocin use by itself has not been proved to ameliorate the negative effect of epidural use on operative birth rates,
which is mediated by prolonged labor (31). Supportive care is a World Health Organization recommended intervention in essential childbirth care, but neither oxytocin augmentation nor epidural use is routinely recommended (32). In light of the association between those interventions and elevated risk of postpartum hemorrhage in hospital births, which was consistent with previous studies (2,3,9,10,13) and further reflected in substantial although nonsignificant differences in maternal blood transfusion rates, efforts should be made to examine the use of oxytocin augmentation and epidural analgesia in Icelandic hospital births. Low operative birth rates in home birth, in spite of signifi-
24 cantly less use of oxytocin and epidural, suggest that the oxytocin and epidural rates in the hospital setting might also be reduced without increasing the overall operative birth rates. Low oxytocin and epidural rates in the home birth group could be partially related to learned behaviors or pre-existing philosophies of the midwives who work in home birth, where those interventions are not available without transfer. If the reasons for the increased use of interventions in the hospitals mainly reside in technocratic institutional cultures (33), institutional changes could suffice to lower intervention rates, but the results of this study indicate that the intervention causality is more complex. Contrary to previous findings (5,7), the duration of the first stage of labor—difficult to adjust for as a result of high missing values—is significantly longer in planned hospital births in Iceland, clinically increasing the need for both oxytocin augmentation and epidural analgesia. If less functional labor in the hospital environment is causing higher intervention rates, reductions in interventions may be facilitated by substantial changes to the hospital birthing environment or increased access to home birth for low-risk women. This study does not add significant findings to the inconsistent knowledge on neonatal outcomes from previous studies. Considering the rarity of adverse neonatal outcomes in low-risk groups, Iceland’s low absolute number of births (23), and the country’s ranking the lowest in neonatal mortality rates in Europe (24), it is unlikely that statistical comparison of neonatal mortality and severe morbidity between service levels in Iceland will be feasible in the near future, even though the incidence of NICU admissions and mild to severe birth-related neonatal morbidity would justify auditing. In the foreseeable absence of conclusive evidence on neonatal outcome, policy on home birth in Iceland and other settings with small absolute home birth numbers might benefit from examining how the inconsistencies of previous studies reflect underlying differences in the structure of services and society. In the Netherlands, Canada, and New Zealand, where neonatal outcomes in home birth are similar to or better than hospital birth outcomes, home birth services are provided by certified midwives and are regulated and integrated into the health care system (6,9,10,18,19). Inconsistent results from the United States, ranging from mild benefits to elevated risk for serious neonatal morbidity in home birth, may reflect lack of regulation and integration within the health care system (12). The current home birth services in Iceland are provided by certified midwives with additional nursing education and are further strengthened by official guidelines on contraindications and transfer indications. Although insignificant and internally inconsistent (with neonatal resuscitation rates higher than the rates of low Apgar
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score, indicating an overuse of this intervention among multiparas in home and hospital birth), the increased rates of low Apgar scores and interventions for the neonates of home birth primiparas suggest that adding official guidelines on perinatal care, including guidelines on neonatal care (34), has the potential to increase home birth safety. Official rather than the current informal integration between home and hospital birth services could further increase consultation and transfer efficiency. Evidence-based guidelines for home birth need to be updated regularly to reflect best practice and current evidence, and would benefit from further studies on the effect of potential influential factors such as parity, contraindications, and quality of services. High transfer rates in Icelandic home birth are consistent with transfer rates in settings with high home birth rates like the United Kingdom and Canada (4,10), but warrant further inspection of transfer indication and effect. The issue of increased distance from place of birth to an obstetric institution, which appears to be related to negative maternal and neonatal outcomes in previous studies (35,36), would need to be studied in Iceland, which is a sparsely populated country with challenging terrain. Furthermore, the association between postpartum hemorrhage, oxytocin augmentation, and epidural analgesia in this study leaves room for the influence of women’s intervention preferences on postpartum hemorrhage rates, suggesting a need for studies on women’s attitudes toward home birth and interventions. Quantitative and qualitative studies on Icelandic families’ experiences and psycho-social outcomes after home and hospital birth would also add valuable information on home birth in Iceland. The present study had limited power to detect small differences in variables with low incidences, which may explain why differences in previous studies, such as reduced rates of perineal injury and other maternal morbidity indicators (2–6,8–11), were not detected. In spite of relatively high birth and home birth rates in Iceland, the country’s small absolute numbers of births (< 5,000 a year (23)) make it difficult to obtain large study groups. In the absence of randomization, a method which is not feasible in home birth studies (37), self-selection bias could not be avoided. The results of the study cannot therefore be directly generalized to other populations, but can nevertheless be indicative of home birth outcomes in many settings with a similar structure of service and society. The strength of the study was its ability to obtain the total national population of Icelandic home births, to exclude unplanned and unattended home births, and to include planned home births that ended in hospital after transfer. The study also had a rigorous process of data collection, matching, exclusion, and adjustment to increase reliability and validity. As a result of low
25
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absolute birth numbers in Iceland, not all home births with rare contraindications were successfully matched, resulting in a skewed hospital birth group with lower rates of contraindications. This skewness was addressed by using two separate approaches in the analysis, one of which excluded all contraindication cases and their matches. The two approaches in the analysis had similar trends and significance. Those working in childbirth services have an obligation to provide evidence-based services, guidelines, and information to women choosing their place of birth, and to respect that the choice is theirs. This study adds to the body of evidence suggesting that planned home birth for low-risk women is as safe as planned hospital birth, facilitating women’s informed choice. Further development of Icelandic home and hospital birth services and future studies on women’s attitudes and other influential factors such as parity, residence, and contraindications are recommended.
Acknowledgments This study was supported by grants from The Icelandic Research Fund for Graduate Students, the Memorial Fund for Midwife Bjorg Magnusdottir, and Farmer Magnus Jonasson and the Icelandic Midwives’ Association’s Research Fund. The authors thank Dr. Arna Hauksd ottir and pediatrician Þ orður Þ orkelsson for methodological assistance, Dr. Gunnar Stefansson and Sigr un Helga Lund for statistical assistance, and Neal O’Donoghue for proofreading. The results of the study were partially presented on June 2, 2014, at the International Confederation of Midwives 30th Triennial Congress in Prague (session C 016, presentation C 047).
References 1. Olsen O, Clausen JA. Planned hospital birth versus planned home birth. Cochrane Database Syst Rev 2012;9:Cd000352. 2. de Jonge A, Mesman JA, Manni€en J, et al. Severe adverse maternal outcomes among low risk women with planned home versus hospital births in the Netherlands: Nationwide cohort study. BMJ 2013;346:f3263. 3. Blix E, Huitfeldt AS, Øian P, et al. Outcomes of planned home births and planned hospital births in low-risk women in Norway between 1990 and 2007: A retrospective cohort study. Sex Reprod Healthc 2012;3(4):147–153. 4. Brocklehurst P, Hardy P, Hollowell J, et al. Perinatal and maternal outcomes by planned place of birth for healthy women with low risk pregnancies: The birthplace in England national prospective cohort study. BMJ 2011;343:d7400. 5. Chang JJ, Macones GA. Birth outcomes of planned home births in Missouri: A population-based study. Am J Perinatol 2011;28 (7):529–536.
6. Davis D, Baddock S, Pairman S, et al. Planned place of birth in New Zealand: Does it affect mode of birth and intervention rates among low-risk women? Birth 2011;38(2):111–119. 7. Wax JR, Pinette MG, Cartin A, Blackstone J. Maternal and newborn morbidity by birth facility among selected United States 2006 low-risk births. Am J Obstet Gynecol 2010;202(2):152.e1–5. 8. Kennare RM, Keirse MJ, Tucker GR, Chan AC. Planned home and hospital births in South Australia, 1991-2006: Differences in outcomes. Med J Aust 2010;192(2):76–80. 9. Janssen PA, Saxell L, Page LA, et al. Outcomes of planned home birth with registered midwife versus planned hospital birth with midwife or physician. CMAJ 2009;181(6–7):377–383. 10. Hutton EK, Reitsma AH, Kaufman K. Outcomes associated with planned home and planned hospital births in low-risk women attended by midwives in Ontario, Canada, 2003-2006: A retrospective cohort study. Birth 2009;36(3):180–189. 11. Lindgren HE, Radestad IJ, Christensson K, Hildingsson IM. Outcome of planned home births compared to hospital births in Sweden between 1992 and 2004. A population-based register study. Acta Obstet Gynecol Scand 2008;87(7):751–759. 12. Cheng YW, Snowden JM, King TL, Caughey AB. Selected perinatal outcomes associated with planned home births in the United States. Am J Obstet Gynecol 2013;209(4):325.e321-328. 13. Nove A, Berrington A, Matthews Z. Comparing the odds of postpartum haemorrhage in planned home birth against planned hospital birth: Results of an observational study of over 500,000 maternities in the UK. BMC Pregnancy Childbirth 2012;12 (1):130. 14. Davis D, Baddock S, Pairman S, et al. Risk of severe postpartum haemorrhage in low-risk childbearing women in New Zealand: Exploring the effect of place of birth and comparing third stage management of labour. Birth 2012;39(2):98–105. 15. Malloy MH. Infant outcomes of certified nurse midwife attended home births: United States 2000 to 2004. J Perinatol 2010;30 (9):622–627. 16. Grunebaum A, McCullough LB, Sapra KJ, et al. Apgar score of 0 at 5 minutes and neonatal seizures or serious neurologic dysfunction in relation to birth setting. Am J Obstet Gynecol 2013;209(4):323.e321-326. 17. Grunebaum A, McCullough LB, Sapra KJ, et al. Early and total neonatal mortality in relation to birth setting in the United States, 2006–2009. Am J Obstet Gynecol. 2014;211(4):390.e1–7. 18. van der Kooy J, Poeran J, de Graaf JP, et al. Planned home compared with planned hospital births in the Netherlands: Intrapartum and early neonatal death in low-risk pregnancies. Obstet Gynecol 2011;118(5):1037–1046. 19. de Jonge A, van der Goes BY, Ravelli AC, et al. Perinatal mortality and morbidity in a nationwide cohort of 529,688 low-risk planned home and hospital births. BJOG 2009;116(9):1177– 1184. 20. Chervenak FA, McCullough LB, Arabin B. Obstetric ethics: An essential dimension of planned home birth. Obstet Gynecol 2011;117(5):1183–1187. 21. Symon A, Winter C, Donnan PT, Kirkham M. Examining autonomy’s boundaries: A follow-up review of perinatal mortality cases in UK independent midwifery. Birth 2010;37(4):280–287. 22. Embaetti landlaeknis. Hlutfall heimafaedinga af ollum faedingum a Islandi 1980-2010 [Home Birth Rates in Iceland 1980-2010] [Internet]. Reykjavik: Embaetti Landlaeknis; 2012. Icelandic. Accessed November 25, 2014. Available at: http://www.landlaeknir.is/servlet/file/store93/item4245/version8/fileservice66/4245_66_ preview.pdf. 23. Bjarnadottir RI. Yfirlit yfir faedingar arid 2012 [A Summary of Births in 2012]. In: Bjarnadottir RI, Gardarsdottir G, Smarason AK, Palsson GI, eds. Skyrsla fra Faedingaskraningunni Fyrir
BIRTH 42:1 March 2015
26
24.
25.
26.
27.
28.
29.
30.
31.
32.
Arid 2012 [Birth Registry Rapport for the Year 2012]. Reykjavik: Landspitali, Kvenna- og barnasvid, 2013:4–7. Icelandic. EURO-PERISTAT Project with SCPE and EUROCAT. European Perinatal Health Report. The health and care of pregnant women and babies in Europe in 2010. Paris: EURO-PERISTAT Project; 2013. Accessed November 25, 2014. Available at: www. europeristat.com. Lindgren H, Kjaergaard H, Olafsdottir OA, Blix E. Praxis and guidelines for planned homebirths in the Nordic countries - an overview. Sex Reprod Healthc 2014;5(1):3–8. Landlaeknisembaettid. Leidbeiningar um val a faedingarstad [Guidelines for Choice in Place of Birth]. Reykjavik: Landlaeknisembaettid; 2007. Icelandic. Halfdansdottir B [Giving birth at home – risk or reward? Comparing the outome of planned home and hospital birth in Iceland 2005-2009: A retrospective case-control pilot study]. Ljosmaedrabladid 2011;89(2):6–12. Icelandic. Brown HC, Paranjothy S, Dowswell T, Thomas J. Package of care for active management in labour for reducing caesarean section rates in low-risk women. Cochrane Database Syst Rev 2013;9:Cd004907. Hodnett ED, Gates S, Hofmeyr GJ, Sakala C. Continuous support for women during childbirth. Cochrane Database Syst Rev 2013;7:Cd003766. Wei S, Wo BL, Qi HP, et al. Early amniotomy and early oxytocin for prevention of, or therapy for, delay in first stage spontaneous labour compared with routine care. Cochrane Database Syst Rev 2013;8:Cd006794. Costley PL, East CE. Oxytocin augmentation of labour in women with epidural analgesia for reducing operative deliveries. Cochrane Database Syst Rev 2013;7:Cd009241. World Health Organization. WHO Recommended Interventions for Improving Maternal and Newborn Health: Integrated management of pregnancy and childbirth [Internet]. 2nd ed. Geneva: WHO
33.
34. 35.
36.
37.
Press; 2009. Accessed November 25, 2014. Available at: http:// whqlibdoc.who.int/hq/2007/WHO_MPS_07.05_eng.pdf?ua=1. Davis-Floyd R. The technocratic, humanistic, and holistic paradigms of childbirth. Int J Gynaecol Obstet 2001;75(Suppl 1):S5– S23. Committee on Fetus and Newborn. Planned home birth. Pediatrics 2013;131(5):1016. Engjom H, Morken NH, Norheim O, Klungsoyr K. Availability and access in modern obstetric care: A retrospective populationbased study. BJOG 2014;121(3):290–299. Ravelli AC, Jager KJ, de Groot MH, et al. Travel time from home to hospital and adverse perinatal outcomes in women at term in the Netherlands. BJOG 2011;118(4):457–465. Hendrix M, Van Horck M, Moreta D, et al. Why women do not accept randomisation for place of birth: Feasibility of a RCT in the Netherlands. BJOG 2009;116(4):537–542; discussion 542– 534.
Supporting Information Additional Supporting Information may be found in the online version of this article: Appendix 1. Contraindications for Home Births and Hospital Births Matching Low-Risk Home Births. Appendix 2. ICD-10 Diagnoses Categorized as Maternal Morbidity in the First Week Postpartum. Appendix 3. ICD-10 Diagnoses Categorized as Birth Related Neonatal Morbidity in the First Week Postpartum.
