Perceptions and motivations of an Australian cohort of women with or without congenital heart disease proceeding to pregnancy Kylie Ngu, Margaret Hay, Samuel Menahem PII: DOI: Reference:
S0020-7292(14)00243-4 doi: 10.1016/j.ijgo.2014.03.032 IJG 7977
To appear in:
International Journal of Gynecology and Obstetrics
Received date: Revised date: Accepted date:
19 November 2013 12 March 2014 11 May 2014
Please cite this article as: Ngu Kylie, Hay Margaret, Menahem Samuel, Perceptions and motivations of an Australian cohort of women with or without congenital heart disease proceeding to pregnancy, International Journal of Gynecology and Obstetrics (2014), doi: 10.1016/j.ijgo.2014.03.032
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ACCEPTED MANUSCRIPT CLINICAL ARTICLE Perceptions and motivations of an Australian cohort of women with or without
a
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Kylie Ngu a, Margaret Hay b, Samuel Menahem c,d,e,*
Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne,
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Melbourne, Australia
Health Professions Education and Educational Research (HealthPeer), Faculty of
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b
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congenital heart disease proceeding to pregnancy 1
Medicine, Nursing and Health Sciences, Monash University, Melbourne, Australia Monash Heart, Monash Medical Centre, Melbourne, Australia
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Department of Obstetrics and Gynecology, Monash University, Melbourne,
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c
Australia
School of Psychology and Psychiatry, Monash University, Melbourne, Australia
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* Corresponding author: Samuel Menahem Monash Medical Centre, 246 Clayton Road, Clayton, Victoria 3168, Australia. Tel.: +61 3 9594 6666; fax: +61 3 9576 1352. E-mail address:
[email protected] 1
Presented in part at the 6th World Congress of Paediatric Cardiology and Cardiac
Surgery, Cape Town, South Africa, February 7–22, 2013.
Keywords: Congenital heart disease; Motherhood; Motivation; Pregnancy; Risk
ACCEPTED MANUSCRIPT Synopsis: Women with congenital heart disease (CHD) had poor understanding of the increased risks associated with pregnancy and had similar motivations for
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conceiving as women without CHD.
ACCEPTED MANUSCRIPT ABSTRACT Objective: To assess the perceptions of women with congenital heart disease (CHD)
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regarding the severity of their cardiac abnormality and its implications in pregnancy,
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and whether their motivations to conceive were similar to those of women without
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CHD.
Methods: A retrospective descriptive study of a cohort of women with (n=20) or without (n=20) CHD, aged over 18 years, who had had one or more successful
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pregnancies. The women were surveyed using a semi-structured questionnaire and
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their medical records were reviewed. Data were analyzed using thematic analysis. Results: Women with CHD were concerned about the health risks associated with their CHD; however, they were not deterred from conceiving because 10 out of 20
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women had a tendency to downplay the seriousness of their CHD. The women’s motivations to conceive were similar in both groups.
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Conclusion: Although women with CHD were clinically identified as an at-risk group, with possible health complications for themselves and their infant, it was ultimately
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the women’s inaccurate perception of the severity of their CHD and of the associated potential health risks that influenced their decision to pursue motherhood. This emphasizes the need for clinicians to have detailed knowledge of the cardiac abnormality and its implications in pregnancy.
ACCEPTED MANUSCRIPT 1. Introduction Medical advances have improved the outcomes of infants and children with
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congenital heart disease (CHD). Their increased survival into adult life requires
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expert care as they face unprecedented challenges [1]. An increasing number of
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women with CHD are now reaching reproductive age and are keen to conceive and complete a pregnancy, posing health risks to themselves and to their unborn child. In general, a woman’s decision to conceive and complete a pregnancy is influenced by
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multiple factors [2–5].
Hemodynamic changes occur in women during pregnancy as their bodies adapt to
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new demands [6]. These changes include an increased blood volume, stroke
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volume, and a heightened heart rate, increasing left ventricular mass and cardiac output by up to 50% [7]. Pregnant women have to accommodate the dramatic
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hemodynamic shifts that occur with the rapid growth of the fetus, and during labor and delivery [8–10]. Despite improved surgical outcomes in CHD patients, residual
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or secondary lesions may contribute toward a limited physiological capacity [11,12].
The decision to conceive and to continue with a pregnancy is a unique and constantly evolving process [13]. Women with CHD have additional problems, over and above the risks of pregnancy that affect all women [14]. CHD has been associated with significant complications in pregnancy, including increased maternal morbidity and mortality, a greater number of spontaneous abortions, early onset of labor, and higher neonatal morbidity and mortality [15–17]. The odds of women with CHD delivering an infant with CHD is four to six times higher than for women that do not have CHD [15], and the risk for some genetically inherited heart diseases is
ACCEPTED MANUSCRIPT higher (up to 50%), such as the heart defects that may arise as part of an autosomal
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dominant inherited syndrome [18].
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Given the inherent risks associated with pregnancy, the aim of the present study was
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to determine the perceptions and motivations of a cohort of women with CHD who had decided to proceed with a pregnancy and had successfully completed it. Their motivations were compared with a cohort of women who did not have CHD and had
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also successfully completed a pregnancy.
2. Materials and methods
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A retrospective descriptive study of a cohort of women with (n=20) or without CHD
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(n=20), aged over 18 years, who had had one or more successful pregnancies. The 40 women fitting the selection criteria were enrolled in the study between September
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10, 2010, and February 11, 2011. The group with CHD comprised patients under the care of one or more cardiologists at Monash Medical Centre, Clayton, Victoria,
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Australia. The group without CHD were volunteers who had attended the same Centre either for a routine review or because their infant or child had a minor illness. Exclusion criteria were women who were deemed by their clinicians to be too emotionally or physically unwell to be interviewed; had had their pregnancy terminated; were initially advised not to conceive because of their CHD; were unable to speak English fluently; or had an intellectual disability. All participants gave informed consent before the study began. A questionnaire was used to gather demographic and clinical details from each participant. Ethics approval was obtained from Monash Medical Centre and the University of Melbourne.
ACCEPTED MANUSCRIPT A semi-structured interview was developed to explore the aims of the study with flexibility to allow emerging key themes to be followed. The participants were asked
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questions about their reasons for deciding to conceive and the motivating factors
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they considered important when contemplating their decision. They were also asked
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about their perceptions of the risks associated with their CHD with regard to the pregnancy, themselves, and their infant (see Supplementary Material S1). All the interviews were conducted by the same researcher (K.N.), with guidance and
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feedback from the co-authors. Each interview was audio recorded and lasted
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approximately 30 minutes. Interviews were either conducted face to face (n=22) or via the telephone (n=18) at a time and place that suited the participant. Most of the
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interviews were conducted at the time of enrollment in the study.
The medical records of the women with CHD were reviewed to clarify the diagnosis
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of CHD, previous medical or surgical interventions if any, and their cardiologist’s assessment of the current severity of the heart abnormality. Obstetric outcomes
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were determined without detailed attention to how the pregnancy was conducted because this was not the focus of the study. The participants’ knowledge of their diagnosis and their perception of the severity of their CHD were compared with the information provided by their attending cardiologist.
Thematic analysis was used to develop emerging patterns from the responses. The thematic analysis was conducted using Microsoft Word (Redmond, WA, USA) to code themes, and data were analyzed using SPSS version 18 (SPSS Inc, Chicago, IL, USA). Initial codes were generated whereby interesting features of the interview responses relevant to the research questions were noted. The codes were collated
ACCEPTED MANUSCRIPT into distinctive meaningful themes so that they were internally consistent within the data set. The final dominant themes were selected based on their prevalence or
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significance.
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An independent coder who was not involved in the study read the transcript notes of two women with and two women without CHD and assigned codes. A second independent coder was provided with a 15-minute information session on the coding
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scheme. The two coders compared results and discussed any differences. Overall
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there was a moderate level of agreement between the two coders reviewing the same interviews (approximately 66%). Disagreement between the coders was
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resolved through discussion, resulting in either a code being changed (six instances)
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or a new code being added (15 instances). The codes derived from this process
3. Results
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were then used to guide further coding and collation of themes.
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There were no significant comorbidities except for the CHD. Of the 20 women with CHD, 16 had undergone surgical interventions. All 20 women were the subject of ongoing review by their attending cardiologist. Ten women were classified by their attending cardiologist as having mild hemodynamically significant lesions (e.g. an atrial septal defect), six were classified as moderate (e.g. repaired tetralogy of Fallot with residual mild pulmonary stenosis and moderate incompetence), two as moderate to severe (e.g. a Fontan circulation for a univentricular heart), and two as severe (e.g. moderately severe aortic stenosis) at the onset of pregnancy. The classifications by the attending cardiologists differed from the perception that 10 out of the 20 women in the CHD group had about the severity of their cardiac status
ACCEPTED MANUSCRIPT (Table 1). Clinician ratings indicated that only 50% of CHD participants had mild or residual heart abnormalities; however, the questionnaire responses indicated that
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90% of the women considered themselves as having mild conditions.
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Given the physical strains of pregnancy and childbirth, the main risk under investigation in the study was the risk to the women with CHD. Nevertheless, all but one of the women in the CHD group had fetal cardiac scans. All the scan results
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were reported to be normal. However, one mother was diagnosed with an atrial
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septal defect after delivering an infant with aortic stenosis. Another infant was found to have a moderate-sized ventricular septal defect even though the results of the
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fetal cardiac examination had been normal. Of the 20 women with CHD, 7 had at
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least one preterm birth (before 37 completed weeks of gestation; mean of 38.9 weeks, range, 30−42 weeks), 9 women had a cesarean delivery (one woman had
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three cesareans in total), and 4 women required instrumental intervention during
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labor.
The proportion of cesarean deliveries among the group without CHD in the present study was higher than the group with CHD (85% vs 55%, respectively), but the group without CHD gave birth to more children (17 cesareans from 37 births) and the mean gestational age was 39.1 weeks. The demographic details of both groups are given in Table 2.
Women with CHD proceeding to pregnancy had concerns for their own health and that of their child: 10 women in the CHD group were worried about their own health, and five were explicit about their fear that they would be unable to care adequately
ACCEPTED MANUSCRIPT for their newborn. Uncertainty about the pregnancy outcome was also feared. Eight of the women with CHD raised concerns about the possibility of their infant having
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CHD. Five of these women were clinically rated as having moderate or severe
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cardiac abnormalities. Ten of the women underestimated the severity of their CHD,
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which calls into question the accuracy of the self-reported impact of their cardiac condition on their lives.
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There were four major contributing factors that influenced the women’s perception
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and understanding of their CHD that may have lessened the impact of their CHD, thereby resulting in a similar motivation to proceed with a pregnancy as that for
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women without CHD. These factors were: a reliance on clinicians’ care and a
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dependency on a successful outcome based on improved medical and surgical management; a distorted understanding of their condition; their past experiences of
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(successfully) living with the heart defect and its (non-impact) on their quality of life; and their adaptation to living with CHD, including coping mechanisms of denial and
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underplaying the severity of the heart abnormalities.
Similar factors appeared to have influenced all the women surveyed in their decision to proceed with a pregnancy. Four common themes arose from the interviews: the influence of existing relationships (e.g. from a partner, family, and friends); the woman’s personal goals and desired experiences in life; “biological” influences arising from the women’s reproductive changes as she aged; and the influence of external (cultural, social, and religious) expectations placed on women to have children. Supplementary Material S2 contains more detail from the interviews illustrating each of the common themes.
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The following is a case vignette of a woman aged 30 years with CHD who
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demonstrated a poor understanding of the severity of her CHD and the associated
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risks of pregnancy. She had had multiple surgeries for her double outlet right
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ventricle, ventricular septal defect and “transposition” of great vessels with pulmonary stenosis. Her cardiologist rated her condition as "severe" but after discussion with her obstetrician, her condition was considered stable although she
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would require careful monitoring if she was to conceive. She described her condition
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as mild in severity. She did not provide a definitive diagnosis of her abnormality but instead noted that she had had five heart operations and two aortic valve replacements. Such a discrepancy reflected the woman’s tendency to downplay the
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severity and associated risks of her condition. Indeed, she was so “euphoric” on conceiving and experiencing her pregnancy that she needed to be reminded by her
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obstetrician to return for cardiologic review. When she did return toward the end of the second trimester, she was found to have developed gross dilatation of her
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neoaortic root. She was admitted, rested, commenced on a beta blocker and had a cesarean delivery at 30 weeks of gestation. This was followed by a cardiac catheter and an aortic root replacement [19]. She expressed a strong belief in the skills of her medical team, having confidence in her doctors. Her desire to have her own child overrode the health risks posed by her CHD.
4. Discussion As found in other studies, the women’s personal experience of successfully living with their heart condition influenced their perception of the pregnancy risks. A poor functional status rather than the initial severity of the underlying heart disease can
ACCEPTED MANUSCRIPT have greater adverse effects on a patient’s quality of life [20]. Their low level of concern may in part be a reflection of their poor knowledge and understanding of
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their CHD [17,21].
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Normalization is an important process in coping with CHD [22]. Denial has been noted to be a psychologically dysfunctional state playing a role in reducing potential psychological distress [23]. In the present study, for women with CHD with a desire
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to become mothers, personal concern about the impact of their pregnancy on their
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health did not appear to be strong enough to deter them from proceeding with their pregnancy and none of the women in this selective sample was explicitly advised not
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to conceive.
Only women who had successfully completed a pregnancy were included in the
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present study, thus limiting the findings to women who had a relatively good quality of life with no or limited hemodynamic sequelae arising from their CHD. Our small
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sample size was skewed toward the low risk of having an infant with CHD. Nevertheless, two women had children with CHD even though the fetal cardiac scan results had been normal, lending substance to the women’s concerns of giving birth to a child with a heart abnormality. The women with CHD also had a higher rate of preterm birth (n=7, 35%) and cesarean delivery (n=9, 45%) compared with Australian statistics of 8.2% for preterm birth and 31.5% for cesarean delivery [24]. However, the cesarean delivery rate was also high among the women without CHD.
Both groups appeared to show little difference in their motivations to conceive. The women with CHD perceived their clinicians as a benevolent paternal/maternal figure
ACCEPTED MANUSCRIPT and assumed that because pregnancy had not been "forbidden" by their clinicians that they would be in safe hands if they proceeded with a pregnancy. The women
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believed that any risks would be carefully monitored throughout their pregnancy and
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managed successfully. The women’s heavy reliance on their clinicians’ advice
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makes the clinicians’ understanding of the CHD and associated risks in pregnancy paramount. Even though some of the women had an unrealistic perception and understanding of their CHD and its associated risks in the context of a pregnancy,
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they took responsibility for their heart condition by undertaking appropriate
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precautions and, on the whole, regularly attended clinical review appointments.
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It would be interesting to investigate the effect of maternal parity and the time interval
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between pregnancies to further understand the motivations and perceptions of women with CHD matched with women in a control group that did not have CHD.
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Future studies could include women with CHD who are located in rural areas, or women who were advised against a pregnancy because of the severity of their
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cardiac status, women with CHD who had unsuccessful pregnancies, or women with CHD who were advised to terminate a pregnancy. This last group will generally have more severe cardiac problems and may find it difficult to participate in such a study, posing important ethical issues.
The findings of the present study that some of the women with CHD had a poor understanding of the increased risks they may face with a pregnancy and that they downplayed the seriousness of their CHD suggest that the role of clinicians, both obstetricians and cardiologists, is pivotal in the care of such patients. The clinicians need to be well informed about the prognosis, implications, and consequences of a
ACCEPTED MANUSCRIPT patient’s heart condition on a pregnancy, with an imperative to provide sound advice
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when such patients present seeking a pregnancy.
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Acknowledgments
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Dr Menahem received partial financial support from the Dube Fund and the Chait
Conflict of interest
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The authors have no conflicts of interest.
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Fund.
ACCEPTED MANUSCRIPT References [1]
Baumgartner H, Bonhoeffer P, De Groot NM, Haan F, Deanfield JE, Galie N,
T
et al. ESC Guidelines for the management of grown-up congenital heart disease
Miller WB, Pasta DJ. Behavioral intentions: which ones predict fertilty
SC R
[2]
IP
(new version 2010). Eur Heart J 2010;31(23):2915–57.
behavior in married couples? J Appl Soc Psychol 1995;25:530–55. [3]
Morgan SP. Late nineteenth- and early twentieth-century childlessness. Am J
Thomson E, McDonald E, Bumpass LL. Fertilty desires and fertility: hers, his
MA
[4]
NU
Soc 1991;97(3):779–807.
and theirs. Demography 1990;27(4):579–88.
Pezeshki MZ, Zeighami B, Miller WB. Measuring the childbearing motivation
D
[5]
Sci 2005;37(1):37–53.
Hunter S, Robson SC. Adaptation of the maternal heart in pregnancy. Br
CE P
[6]
TE
of couples referred to the Shiraz Health Center for premarital examinations. J Biosoc
Heart J 1992;68(6):540–3.
Bowater SE, Thorne SA. Management of pregnancy in women with acquired
AC
[7]
and congenital heart disease. Postgrad Med J 2010;86(1012):100–5. [8]
Fujitani S. Hemodynamic assessment in a pregnant and peripartum patient.
Crit Care Med 2005;33(10 Suppl):S354–61. [9]
Abbas AE, Lester SJ, Connolly H. Pregnancy and the cardiovascular system.
Int J Cardiol 2005;98(2):179–89. [10]
Colman JM. Pregnancy in adult patients with congenital heart disease. Prog
Pediatr Cardiol 2003;17(1):53–60. [11]
Uebing A, Steer PJ, Yentis SM, Gatzoulis MA. Pregnancy and congenital
heart disease. BMJ 2006;332(7538):401–6.
ACCEPTED MANUSCRIPT [12]
Drenthen W, Boersma E, Balci A, Moons P, Roos-Hesselink JW, Mulder BJ.
Predictors of pregnancy complications in women with congenital heart disease. Eur
Kilpatrick K, Purden M. Using reflective nursing practice to improve care of
IP
[13]
T
Heart J 2010;31(17):2124–32.
SC R
women with congenital heart disease considering pregnancy. MCN Am J Matern Child Nurs 2007;32(3):140–7. [14]
Somerville J. The Denolin Lecture: The woman with congenital heart disease.
Siu SC, Colman JM, Sorensen S, Smallhorn JF, Farine D, Amankwah KS, et
MA
[15]
NU
Eur Heart J 1998;19(12):1766–75.
al. Adverse neonatal and cardiac outcomes are more common in pregnant women
Siu SC, Sermer M, Colman JM, Alvarez AN, Mercier L, Morton BC, et al.
TE
[16]
D
with cardiac disease. Circulation 2002;105(18):2179–84.
Prospective multicenter study of pregnancy outcomes in women with heart disease.
[17]
CE P
Circulation 2001;104(5):515–21.
Foster E, Graham TP Jr, Driscoll DJ, Reid GJ, Reiss JG, Russell IA, et al.
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Task force 2: special health care needs of adults with congenital heart disease. J Am Coll Cardiol 2001;37(5):1176–83. [18]
Nora JJ. Multifactorial inheritance hypothesis for the etiology of congenital
heart diseases: the genetic-environmental interaction. Circulation 1968;38(3):604– 17. [19]
Hayonki Y, Cochrane AD, Menahem S, Smith JA. Neoaortic root dilatation
with saccular aneurysm formation after arterial switch operation for Taussig-Bing anomaly. J Thorac Cardiovasc Surg 2007;133:569–72. [20]
Moons P. Is the severity of congenital heart disease associated with the
quality of life and perceived health of adult patients? Heart 2005;91(9):1193–8.
ACCEPTED MANUSCRIPT [21]
Wang QF, Hay M, Clarke D, Menahem S. Association between knowledge of
disease, depression and anxiety, social support, sense of coherence and optimism
T
with health related quality of life in an ambulatory sample of adolescents with heart
Claessens P. What does it mean to live with a congenital heart disease? A
SC R
[22]
IP
disease. Cardiol Young 2014;24(1):126–33.
qualitative study on the lived experiences of adult patients. Eur J Cardiovasc Nurs 2005;4(1):3–10.
Livneh H. Denial of chronic illness and disability: Part II. research findings,
NU
[23]
MA
measurement considerations, and clinical aspects. Rehabil Couns Bull 2009;53(1):44–55.
Australian Institution of Health and Welfare. Australia's mothers and babies
D
[24]
TE
2009. Canberra: Perinatal Statistics Series no. 25. Cat. no. PER 52. http://www.aihw.gov.au/publication-detail/?id=10737420870. Published December
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21, 2011. Accessed April 28, 2014.
ACCEPTED MANUSCRIPT Table 1 Clinicians’ and participants’ diagnosis and severity rating of participants’ congenital heart disease. Participants' perceptions of CHD concordant with cardiologists’ assessment Participant’s perception of severity of their CHD
Clinician’s assessment of severity of participants’ CHD
Pulmonary atresia, VSD, MAPCAs Mitral valve incompetence
Pulmonary atresia/VSD/MAPCAs
Yes
Mild
Mild
Mitral valve dysplasia
No
Hole in the heart
VSD, ASD
Transposition of the great vessels Coarctation of aortic valve
Transposition of the great vessels Coarctation of aorta, mild aortic stenosis Bicuspid aortic valve and coarctation of aorta Ebstein anomaly of tricuspid valve
Heart disorder
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Mild
Yes
Mild
Mild
Yes
Mild
Mild
Yes
Mild
Mild
Yes
Mild
Mild
Yes
Mild
Mild
No
Mild
Mild
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Bicuspid aortic valve and coarctation of aorta
Mild
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Participant’s perception of their diagnosis
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Clinician’s diagnosis
Surgery prior to pregnancy
ASD
VSD with mild aortic incompetence
VSD, mild aortic regurgitation
No
Mild
Mild
Tetralogy of Fallot
Tetralogy of Fallot
Yes
Mild
Mild
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ASD
Heart murmur
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Participants’ perceptions of CHD discordant with cardiologists’ assessment
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Congenital heart disease Heart condition
Transposition of the great vessels Double inlet left ventricle, Fontan Transposition of the great vessels, VSD, pulmonary stenosis
Moderate /severe Moderate /severe
Yes
Mild
Yes
Mild
Yes
Mild
Moderate
Tetralogy of Fallot
Tetralogy of Fallot
Yes
Mild
Moderate
Hole in heart
Tetralogy of Fallot
Yes
Mild
Moderate
Aortic stenosis
Aortic valve stenosis
No
Mild /moderate
Moderate
Yes
Mild
Severe
Yes
Mild
Moderate
Transposition of the great vessels
Double outlet right ventricle, subpulmonary VSD, pulmonary stenosis Transposition of the great vessels
VSD, aortic stenosis
VSD, aortic stenosis
Yes
Moderate /severe
Severe
Subaortic stenosis
Subaortic stenosis
Yes
Mild
Moderate
Open heart operations ×5, aortic valve replacement ×2
Abbreviations: ASD, atrial septal defect; CHD, congenital heart disease; MAPCAs, major aortopulmonary collateral arteries; VSD, ventricular septal defect.
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Table 2 Biographical summary of women with and without congenital heart disease. Women with CHD (n=20) Women without CHD (n=20) Age, y 32.6 ± 5.3 33.9 ± 5.2 Marital status Married 12 13 Living together, not married 4 5 Single 4 1 Unknown 0 1 Employment status Employed 13 14 Unemployed 2 3 Unpaid work 5 2 Unknown 0 1 Highest level of education Tertiary 11 17 High school 8 2 Unknown 1 1 Number of children 1 10 12 2 6 3 3 4 3 4 or more 0 2 Mean gestational age, wk 38.9 39.1 Mode of delivery (n(children)=28) (n(children)=37) Vaginal Spontaneous 11 17 Forceps 4 0 Vacuum extraction 0 2 Emergency cesarean 3 9 Elective cesarean 8 8 Not available 2 1 CHD in children 2 0 Abbreviation: CHD, congenital heart disease.