AUSI NZ J Ohsier Gynaecol 1991: 31: 4: 291
THE AUSTRALIAN & NEW ZEALAND JOURNAL OF
OBSTETRICS & GYNAECOIQGY
November, 1991
vbl. 31
- NO.4
Teenage Pregnancy in South Australia, 1986-1988 h o p i n g Zhang' and Annabelle C h a d
Queen Victoria Hospital (A Division of The Adelaide Medical Centtefor Women and Childten)', and South Austmlian Health Commission,' Adelaide
EDI'IORIAL COMMENI! Readers please note that this paper on teenage pregnancy has the unique quality of comingfrom the only Austmlian State in which it is a statutory requirement to notify all cases of termination of pegnancy. The authors have then$om been able to ptvvide important idormation mgading the chamcterirtics of ptegnant teenagers and the changing incidence of abortion as well m the obstetric m l t s in continuing pregnancies These data allow deductions concerning teenage behaviour m l t i n g in pregnancy. The results identifv subgmujx of our population who requite special counwlling and cam Hopefully the Council members of the Royal Austmlian College of Obs&trikiansand Gymnmlogkts will use their irtfluence to emunrge all State Fbrliaments to intraluce legislation requiring noti3cation of all cases of termination of pregnancy. Weneed thefocts to identifythe high risk g a p , so that available m u m can be apptvpriately dimted. Summary: Teenage pregnancies accounted for 6.0% of confinements and 24.8% of legal abortions in South Australia in 198&1988. The teenage pregnancy rate has declined by 28.5% since the early 1970s. associated with a 52.6% decline in the confinement rate The abortion rate rose in the 1970s but fell slightly in the 1980s; nearly half the teenage pregnancies now end in legal abortion: abortion was a more likely pregnancy outcome for younger teenagers and for teenagers resident in metropolitan areas. Compared with women confined in their twenties, confined teenagers were more likely to be single, primigravid and Aboriginal, to have few antenatal visits and to have a medical or obstetric complication during their pregnancy. They were less likely to have an induction of labour o r an elective Caesarean section. They had higher frequencies of preterm deliveries (8.9%) and low birth-weight babies (9.3vo). The youngest teenagers had the most risk factors and the worst outcomes. In the small group of Aboriginal teenagers aged 16 years and under, about a third of the babies were low birth-weight or premature and one in 12 babies was a perinatal death. Comparison of singleton pregnancies of teenagers with women in their twenties all of whom were single, Caucasian and primigravid, with 7 or more antenatal visits, showed similarity in outcomes. This suggests that being teenage is not in itself a risk factor. Continued support and extension of teenage counselling and antenatal care services is essential.
Addms for correspondence: Dr. A. Chan. Pregnancy Outcome Unit, S.A. Health Commission, Citi Centre Building, I1 Hindmarsh Squaw Adelaide, South Australia. 5ooo.
1. WHO Visiting Scholar in %natal Epidemiology, Dcpartmcnt of
Obstetrics and Gynaecology, University of Adelaide 2. Senior Consultant, Pregnancy Outcome Unit, Epidemiology Branch.
AUST. .AND N.Z. JOURNALOF OBSTETRICS AND GVNAECOLOGY
292
provided since 1981 by South Australian midwives and neonatal nurses on all births of at least 400 g birthweight or, where birth-weight was unavailable, 20 weeks' gestation, to the Pregnancy Outcome Unit of the South Australian Health Commission. Data on abortions performed in South Australia have been provided by doctors since 1970 when abortion was legalized under the Criminal Law Consolidation Act. South Australia has a population of 1.4 million and approximately 4,000 legal abortions and 20,000 births annually in the 1986-1988 period. Population data and data on the numbers of confinements in South Australia for the years 1970-1989 are from the Australian Bureau of Statistics. As statistics on spontaneous abortions are incomplete, pregnancies have been based only on confinements and induced abortions, and pregnancy rates calculated are therefore a slight underestimate. This study is descriptive, but comparisons have been drawn between the pregnancies of 3,483 teenagers in 1986-1988 and 11,740 women aged 20-29 years who gave birth in 1987. These numbers represented all the confinements to these age groups in those years recorded in the perinatal data collection. in these comparisons and those between Aboriginal and Caucasian teenagers, relative risks and their 95% confidence limits have been calculated for a range of factors using Epi Info, Version 5 (13).
Teenage pregnancy has serious consequences for the individual and the community. This is related to the characteristics which distinguish pregnant teenagers from their peers and other pregnant women. As a group they frequently come from a deprived social and economic background (42); from families with single parents, a lack of affection or a history of teenage pregnancy; there is frequently low self-esteem and risktaking behaviour (1). Pregnancy results in an interruption of the teenager's education or training and tension and instability in relationships with her family of origin and her partner. The children of these pregnancies may be adversely affected in their cognitive, social and emotional development and their achievement (3). The effects on society stem from the high level of unemployment (2) in an educationally-disadvantaged group, who require financial and psychosocial support (3). In Australia in 1985-1986, there was an average of 6,500 teenage mothers receiving Supporting Parents' Benefits at a cost of A W . 3 million (4). The obstetric outcomes of teenage pregnancies have been shown to be poorer than for non-teenage pregnancies. Higher incidences of low birth-weight (5-8), prematurity (5) and perinatal mortality (6,8) have been reported. Lack of antenatal care is a feature of teenage pregnancy (7) and several researchers have concluded that it is this lack, with failure to identify risk factors that has led to the poor outcomes ($9-11). Thus it has been argued that it is not the biological immaturity of the teenagers but their low socioeconomic level and lack of antenatal care that has resulted in the poor outcomes. In Australia, teenage births reached a peak in the early 1970s and have been declining since (4). As elsewhere, abortion has reduced the total teenage births (4,7,12). The present study reviews the characteristics and outcomes of teenage pregnancies in South Australia in 1986-1988. Comparisons are drawn with the findings of an earlier report on teenage pregnancies in 1981-1983 (7) to detect any trends over the 1980s.
RESULTS
I. Incidence of Teenage Pnegnancies Between 1970-1974 and 1985-1989. there was a gradual decline from 12.6% to 9.4% in teenage pregnancies (ages 13-19 years) as a proportion of all pregnancies in South Australia (table 1). This corresponded with a decline of 28.5% in the pregnancy rate per 1,OOO women aged 15-19 years (from 53.6 to 38.3 per 1,OOO women) (table 2 and figure 1). The decline in the confinement rate between those 2 5-year periods was 52.6%. Over the same period of time, the abortion rate first rose but then tended to fall in the 1980s. The year 1970 was the first year of legal abortion in South Australia and the numbers of notified abortions rose dramatically in the subsequent 10 years. The proportion of teenage pregnancies which were terminated rose from 21% in 1970-1974 to 48% in 1985-1989 (table 1).
MATERIALS AND METHODS The data used for analysis of characteristics of teenage pregnancies in 1986-1988 have been obtained from the South Australian perinatal data collection and the abortion statistics collection. Perinatal data have been
Table 1. Teenage Pregnancies (Age 13-19 Years) as a Proportion of SA Pregnancies. 1970-1989 Teenage confinements 5-year period 1970- 1974 1975-1979 1980- 1984 1985-I989
No. 1 1,742
8,727 6,910 5,775
Yo of all confinements ( I I . 1%) (9.3%) (7.3%) (6.0%)
Tixnane pregnancies
Teenage abortions of all abortions (27.5%) (31.7%) (29.1%) (24.6%) or0
No. 3,125 5,001 5,756 5,228
of all pregnancies (12.6%) (12.5qo) 070
No.
14,867 13,728 12.666 11.003
(11.1%)
(9.4Vo)
Teenage abortions as a percentage of teenage pregnancies 21% 364'0 4SWO
48ob
Source: I. Australian Bureau of Statistics: Births Australia 1970-1989. 2. Reports o f the Committee appointed to examine and report on abortions notified in South Australia for the pars 1970-1989.
Prcgnmcy bra h t b A.rtrdb. 191c1969 (Age 15-19 years) ( R a I a per 1.OOO women aged 15-19 years)
Table 2. T-p
Teenage confinements
5 - y period 1970-1974 1975-1979 1980-1984 1985-1989
TiXMge
abortions
T-wc pregnan-
No.
Rate
Na
Rate
Na
Rate
11,682 8.651 6,871 5.737
42.6
3.018 4,850 5.598 5.116
11.0 16.3 19.9 18.0
14,700 13.501 12.469 10.853
53.6 45.2 44.3 38.3
29.0 24.4
20.2
Cmrd rrgiom Central Northern Central W e r a central Eastcra Central Southern Country mgionr Mikc & Lorn North
Soum: 1. A l s t m h l &tmuof S I U i s t k Birthskrstrplia 1970-1989. 2. Reports of the Committee appointed to ournine and rrport on abortions notitied in Swth Aurlnlia for the years 1970-1989. 3. Euinuted Resident Paputation by Sex and Age: States imdTmitorier of Australia JUM 1971 to June 1981. June 1981 10 June 1987.
Mumylands south East EyrC
Northern South AustrPlia
+. \,
0 -. 1970-74
1975-79 1980-84 5 yew period
19.5 22.9 15.6 18.7
44.9 41.7
20.9 28.1 27.5 35.9 40.9 20.5
16.6 13.2 16.6 13.5 18.0 18.7
37.4 41.3 44.1 49.3 58.9 39.2
25.0
33.7
country regions and 4 Central regions which have a major metropolitan component (figure 2). The highest teenage pregnancy rates were in the country regions:the Northern Region (58.9pngnanCies per 1.OOO women aged 15-19years) and E y n (49.3 per l.OO0 women) (table 4). Among the Central regions, the highest pregnancy rates were in the Central Northern Region (with 44.9 per 1,OOO women) and the Central Western Region (with 41.7 per 1,OOO women). These 2 Central regions have been demonstrated to haw populations of lower socioeconomic status in their metropolitan component than the remainiog2 Central regions (14).The lowest pregnancy rate of 25.0per 1.OOO women was recorded in the highest socioeconomic Central Eastern Region. This region, however, had the highest proportion of teenage pregnancies ending in abortion - 62%, compared with 2 7 % 4 % in the country regions. Related to this is the finding that married women and women in de facto relationships contributed to a larger proportion of teenage pregnancies in the country regions than in the Central regions (33.7% versus 21.8%).
Rate per 1000 women aged 1s-18 yeera
so,
50’-
25.4 18.8 9.4 14.9
1985-89
Figure 1. Tecnage pregnancy rates. South Australia. 1970-1989 (Age 15-19 by 5 ~CriodS).
2. Sociodernogmphic Chomcteristics (a) Age Dtktribution The age distribution of teenage pregnancies (table 3) shows the numbers of births and abortions increasing with age, with 17.2% of those pregnant being under 17 years of age while a third were aged 19 years. While less than half of the pregnancies at ages 18 and 19 ended in abortions, the reverse was true for pregnancies under 18 years; the younger the teenager, the more likely it was for a pregnancy to end in abortion.
(4Race The teenage confinement rate for Aboriginals, at 93.6 per 1,OOO women aged 15-19years, was nearly 5 times higher than for non-Aboriginals (205per 1,OOO women). Statistics on race are not available from the abortion statistics collection for comparison. Aboriginals contributed 7.5% to teenage confinements compared with 1.9% to Confinements of women aged 20-29 years (table 5).
(b) Regional m t a South Australia has been divided by the Committee on Uniform Regional Boundaries (CURB) into 5 T a w 3. Age DLslribulloa of Abortions
Confinements
(%I
Pregnancies
Abortions as a proportion of pregnancies
(9e)
No.
13 14 I5 16 17 18 19
2 20 102 293 67 1 1,039 1.356
(0.1%) (0.6s) (2.9%) (8.4%) (19.376) (29.8%) 138.9%)
I2 55 209 450 708 886 861
(0.4%) (1.7%) (6.6%) (14.1 %) (22.3%) (27.8%) (27.1%)
14 75 31 1 743 1,379 1,925 2,217
(4.7%) ( I I .1%) (20.7%) (28.9%) (33.3%)
46% 39%
Total
3,483
(100.0%)
3,181
(100.0%)
6.664
(100.0%)
48%
No.
No.
(VD)
(0.2%) (1.1%)
86% 73% 67% 61% 51%
A U S . AND N.Z.
294
JOURNAL OF OBsrETRICs AND GYNAECOUXY
(d) Marital status The majority of the teenagers (58.lVo) who were confined in South Australia in 1986-1988 were single women ( i a women who were not married or in a de fact0 relationship). Thisproportion has increased from 50.6% in 1981-1983 (7), and is much higher than the proportion of single women confined in the age group 20-29 years (13.0%) (table 5).
(e) Occupation Five percent of teenagers gave their occupation as student and 17.1% as unemployed, whereas 32.2% were housewives. The proportion of unemployed increased from 14.5% in 1986to u).6% in 1988. There is, however, some difficulty in categorizing teenagers by occupation. Harris et a1 (2) reported that teenagers tended to be categorized by others as ‘home duties’ when they considered themselves as unemployed.
If, Hospital of delivery The distribution of teenage confinements by hospital of delivery was very different from that for confinements to women aged 20-29 years. A larger proportion of teenage confinements took place in metropolitan teaching hospitals (64.8% versus 50.3%) and country hospitals (32.5% versus 28.0%) compared with confinements of women in their twenties. Only 2.7% of teenage confinements occurred in metropolitan private hospitals, compared with 21.7% for the older women.
Figure 2. 1986-1988.
pqpancy
ram in South kunnlianCURB Regions
3. Obstetric Chamcteristics These are compared with those of women in their twenties in table 5 . (a) Fist pregnancy experience For 70.3Vo of the teenagers, this was their first pregnancy and for 23.2% the second. Of those who had had
’hbk 5. lkeaage ConfinclaccltrCompared r i t b Cooflrrmcntr of Women Aged 20-29 Yam, Sooth Amdnlh. 1906-1W l k n a g e women Women aged 2029 w a n Relative risk of characterink Chpnrctcristic (n = 3.483) (n = 11.740) (9% confidence limits)
(Mothers) Ram - Aboriginal Single marital status Private hospital delivery No pmious pregnancy Uncertain of LMP date Antenatal visits < 7 Medical condition Obstetric complication Induction of Labour Method of deliwry Spontaneous vaginal Emergency Caesarean Elective Caesartan Other (assisted) Labour or delivery complication
( I .9%) (13.01) (21.7%) (35.1%) (19.4%) (6.1%)* (7.7Qo) (24.8%) (22.6Qr)
4.05 4.47 0.12 2.00 1.94 2.67 1.62 1. I9 0.23
( I . 12.1.26) (0.20.0.27)
(68.2%) 7,594 (64.7%) (11.5%) 1.231 (10.5%) 137 (3.9%) 908 (7.7%) 569 (16.3Qo) 2,007 (17.1%) 1,240 (35.6%) 4,408 (37.51) (Babies) (n = 3.514) (N = ii,sai) Low birth-weight 328 (9.38) 130 (6.1 %) Gestational age
THE AUSTRALIAN & NEW ZEALAND JOURNAL OF
OBSTETRICS & GYNAECOIQGY
November, 1991
vbl. 31
- NO.4
Teenage Pregnancy in South Australia, 1986-1988 h o p i n g Zhang' and Annabelle C h a d
Queen Victoria Hospital (A Division of The Adelaide Medical Centtefor Women and Childten)', and South Austmlian Health Commission,' Adelaide
EDI'IORIAL COMMENI! Readers please note that this paper on teenage pregnancy has the unique quality of comingfrom the only Austmlian State in which it is a statutory requirement to notify all cases of termination of pegnancy. The authors have then$om been able to ptvvide important idormation mgading the chamcterirtics of ptegnant teenagers and the changing incidence of abortion as well m the obstetric m l t s in continuing pregnancies These data allow deductions concerning teenage behaviour m l t i n g in pregnancy. The results identifv subgmujx of our population who requite special counwlling and cam Hopefully the Council members of the Royal Austmlian College of Obs&trikiansand Gymnmlogkts will use their irtfluence to emunrge all State Fbrliaments to intraluce legislation requiring noti3cation of all cases of termination of pregnancy. Weneed thefocts to identifythe high risk g a p , so that available m u m can be apptvpriately dimted. Summary: Teenage pregnancies accounted for 6.0% of confinements and 24.8% of legal abortions in South Australia in 198&1988. The teenage pregnancy rate has declined by 28.5% since the early 1970s. associated with a 52.6% decline in the confinement rate The abortion rate rose in the 1970s but fell slightly in the 1980s; nearly half the teenage pregnancies now end in legal abortion: abortion was a more likely pregnancy outcome for younger teenagers and for teenagers resident in metropolitan areas. Compared with women confined in their twenties, confined teenagers were more likely to be single, primigravid and Aboriginal, to have few antenatal visits and to have a medical or obstetric complication during their pregnancy. They were less likely to have an induction of labour o r an elective Caesarean section. They had higher frequencies of preterm deliveries (8.9%) and low birth-weight babies (9.3vo). The youngest teenagers had the most risk factors and the worst outcomes. In the small group of Aboriginal teenagers aged 16 years and under, about a third of the babies were low birth-weight or premature and one in 12 babies was a perinatal death. Comparison of singleton pregnancies of teenagers with women in their twenties all of whom were single, Caucasian and primigravid, with 7 or more antenatal visits, showed similarity in outcomes. This suggests that being teenage is not in itself a risk factor. Continued support and extension of teenage counselling and antenatal care services is essential.
Addms for correspondence: Dr. A. Chan. Pregnancy Outcome Unit, S.A. Health Commission, Citi Centre Building, I1 Hindmarsh Squaw Adelaide, South Australia. 5ooo.
1. WHO Visiting Scholar in %natal Epidemiology, Dcpartmcnt of
Obstetrics and Gynaecology, University of Adelaide 2. Senior Consultant, Pregnancy Outcome Unit, Epidemiology Branch.
AUST. .AND N.Z. JOURNALOF OBSTETRICS AND GVNAECOLOGY
292
provided since 1981 by South Australian midwives and neonatal nurses on all births of at least 400 g birthweight or, where birth-weight was unavailable, 20 weeks' gestation, to the Pregnancy Outcome Unit of the South Australian Health Commission. Data on abortions performed in South Australia have been provided by doctors since 1970 when abortion was legalized under the Criminal Law Consolidation Act. South Australia has a population of 1.4 million and approximately 4,000 legal abortions and 20,000 births annually in the 1986-1988 period. Population data and data on the numbers of confinements in South Australia for the years 1970-1989 are from the Australian Bureau of Statistics. As statistics on spontaneous abortions are incomplete, pregnancies have been based only on confinements and induced abortions, and pregnancy rates calculated are therefore a slight underestimate. This study is descriptive, but comparisons have been drawn between the pregnancies of 3,483 teenagers in 1986-1988 and 11,740 women aged 20-29 years who gave birth in 1987. These numbers represented all the confinements to these age groups in those years recorded in the perinatal data collection. in these comparisons and those between Aboriginal and Caucasian teenagers, relative risks and their 95% confidence limits have been calculated for a range of factors using Epi Info, Version 5 (13).
Teenage pregnancy has serious consequences for the individual and the community. This is related to the characteristics which distinguish pregnant teenagers from their peers and other pregnant women. As a group they frequently come from a deprived social and economic background (42); from families with single parents, a lack of affection or a history of teenage pregnancy; there is frequently low self-esteem and risktaking behaviour (1). Pregnancy results in an interruption of the teenager's education or training and tension and instability in relationships with her family of origin and her partner. The children of these pregnancies may be adversely affected in their cognitive, social and emotional development and their achievement (3). The effects on society stem from the high level of unemployment (2) in an educationally-disadvantaged group, who require financial and psychosocial support (3). In Australia in 1985-1986, there was an average of 6,500 teenage mothers receiving Supporting Parents' Benefits at a cost of A W . 3 million (4). The obstetric outcomes of teenage pregnancies have been shown to be poorer than for non-teenage pregnancies. Higher incidences of low birth-weight (5-8), prematurity (5) and perinatal mortality (6,8) have been reported. Lack of antenatal care is a feature of teenage pregnancy (7) and several researchers have concluded that it is this lack, with failure to identify risk factors that has led to the poor outcomes ($9-11). Thus it has been argued that it is not the biological immaturity of the teenagers but their low socioeconomic level and lack of antenatal care that has resulted in the poor outcomes. In Australia, teenage births reached a peak in the early 1970s and have been declining since (4). As elsewhere, abortion has reduced the total teenage births (4,7,12). The present study reviews the characteristics and outcomes of teenage pregnancies in South Australia in 1986-1988. Comparisons are drawn with the findings of an earlier report on teenage pregnancies in 1981-1983 (7) to detect any trends over the 1980s.
RESULTS
I. Incidence of Teenage Pnegnancies Between 1970-1974 and 1985-1989. there was a gradual decline from 12.6% to 9.4% in teenage pregnancies (ages 13-19 years) as a proportion of all pregnancies in South Australia (table 1). This corresponded with a decline of 28.5% in the pregnancy rate per 1,OOO women aged 15-19 years (from 53.6 to 38.3 per 1,OOO women) (table 2 and figure 1). The decline in the confinement rate between those 2 5-year periods was 52.6%. Over the same period of time, the abortion rate first rose but then tended to fall in the 1980s. The year 1970 was the first year of legal abortion in South Australia and the numbers of notified abortions rose dramatically in the subsequent 10 years. The proportion of teenage pregnancies which were terminated rose from 21% in 1970-1974 to 48% in 1985-1989 (table 1).
MATERIALS AND METHODS The data used for analysis of characteristics of teenage pregnancies in 1986-1988 have been obtained from the South Australian perinatal data collection and the abortion statistics collection. Perinatal data have been
Table 1. Teenage Pregnancies (Age 13-19 Years) as a Proportion of SA Pregnancies. 1970-1989 Teenage confinements 5-year period 1970- 1974 1975-1979 1980- 1984 1985-I989
No. 1 1,742
8,727 6,910 5,775
Yo of all confinements ( I I . 1%) (9.3%) (7.3%) (6.0%)
Tixnane pregnancies
Teenage abortions of all abortions (27.5%) (31.7%) (29.1%) (24.6%) or0
No. 3,125 5,001 5,756 5,228
of all pregnancies (12.6%) (12.5qo) 070
No.
14,867 13,728 12.666 11.003
(11.1%)
(9.4Vo)
Teenage abortions as a percentage of teenage pregnancies 21% 364'0 4SWO
48ob
Source: I. Australian Bureau of Statistics: Births Australia 1970-1989. 2. Reports o f the Committee appointed to examine and report on abortions notified in South Australia for the pars 1970-1989.
Prcgnmcy bra h t b A.rtrdb. 191c1969 (Age 15-19 years) ( R a I a per 1.OOO women aged 15-19 years)
Table 2. T-p
Teenage confinements
5 - y period 1970-1974 1975-1979 1980-1984 1985-1989
TiXMge
abortions
T-wc pregnan-
No.
Rate
Na
Rate
Na
Rate
11,682 8.651 6,871 5.737
42.6
3.018 4,850 5.598 5.116
11.0 16.3 19.9 18.0
14,700 13.501 12.469 10.853
53.6 45.2 44.3 38.3
29.0 24.4
20.2
Cmrd rrgiom Central Northern Central W e r a central Eastcra Central Southern Country mgionr Mikc & Lorn North
Soum: 1. A l s t m h l &tmuof S I U i s t k Birthskrstrplia 1970-1989. 2. Reports of the Committee appointed to ournine and rrport on abortions notitied in Swth Aurlnlia for the years 1970-1989. 3. Euinuted Resident Paputation by Sex and Age: States imdTmitorier of Australia JUM 1971 to June 1981. June 1981 10 June 1987.
Mumylands south East EyrC
Northern South AustrPlia
+. \,
0 -. 1970-74
1975-79 1980-84 5 yew period
19.5 22.9 15.6 18.7
44.9 41.7
20.9 28.1 27.5 35.9 40.9 20.5
16.6 13.2 16.6 13.5 18.0 18.7
37.4 41.3 44.1 49.3 58.9 39.2
25.0
33.7
country regions and 4 Central regions which have a major metropolitan component (figure 2). The highest teenage pregnancy rates were in the country regions:the Northern Region (58.9pngnanCies per 1.OOO women aged 15-19years) and E y n (49.3 per l.OO0 women) (table 4). Among the Central regions, the highest pregnancy rates were in the Central Northern Region (with 44.9 per 1,OOO women) and the Central Western Region (with 41.7 per 1,OOO women). These 2 Central regions have been demonstrated to haw populations of lower socioeconomic status in their metropolitan component than the remainiog2 Central regions (14).The lowest pregnancy rate of 25.0per 1.OOO women was recorded in the highest socioeconomic Central Eastern Region. This region, however, had the highest proportion of teenage pregnancies ending in abortion - 62%, compared with 2 7 % 4 % in the country regions. Related to this is the finding that married women and women in de facto relationships contributed to a larger proportion of teenage pregnancies in the country regions than in the Central regions (33.7% versus 21.8%).
Rate per 1000 women aged 1s-18 yeera
so,
50’-
25.4 18.8 9.4 14.9
1985-89
Figure 1. Tecnage pregnancy rates. South Australia. 1970-1989 (Age 15-19 by 5 ~CriodS).
2. Sociodernogmphic Chomcteristics (a) Age Dtktribution The age distribution of teenage pregnancies (table 3) shows the numbers of births and abortions increasing with age, with 17.2% of those pregnant being under 17 years of age while a third were aged 19 years. While less than half of the pregnancies at ages 18 and 19 ended in abortions, the reverse was true for pregnancies under 18 years; the younger the teenager, the more likely it was for a pregnancy to end in abortion.
(4Race The teenage confinement rate for Aboriginals, at 93.6 per 1,OOO women aged 15-19years, was nearly 5 times higher than for non-Aboriginals (205per 1,OOO women). Statistics on race are not available from the abortion statistics collection for comparison. Aboriginals contributed 7.5% to teenage confinements compared with 1.9% to Confinements of women aged 20-29 years (table 5).
(b) Regional m t a South Australia has been divided by the Committee on Uniform Regional Boundaries (CURB) into 5 T a w 3. Age DLslribulloa of Abortions
Confinements
(%I
Pregnancies
Abortions as a proportion of pregnancies
(9e)
No.
13 14 I5 16 17 18 19
2 20 102 293 67 1 1,039 1.356
(0.1%) (0.6s) (2.9%) (8.4%) (19.376) (29.8%) 138.9%)
I2 55 209 450 708 886 861
(0.4%) (1.7%) (6.6%) (14.1 %) (22.3%) (27.8%) (27.1%)
14 75 31 1 743 1,379 1,925 2,217
(4.7%) ( I I .1%) (20.7%) (28.9%) (33.3%)
46% 39%
Total
3,483
(100.0%)
3,181
(100.0%)
6.664
(100.0%)
48%
No.
No.
(VD)
(0.2%) (1.1%)
86% 73% 67% 61% 51%
A U S . AND N.Z.
294
JOURNAL OF OBsrETRICs AND GYNAECOUXY
(d) Marital status The majority of the teenagers (58.lVo) who were confined in South Australia in 1986-1988 were single women ( i a women who were not married or in a de fact0 relationship). Thisproportion has increased from 50.6% in 1981-1983 (7), and is much higher than the proportion of single women confined in the age group 20-29 years (13.0%) (table 5).
(e) Occupation Five percent of teenagers gave their occupation as student and 17.1% as unemployed, whereas 32.2% were housewives. The proportion of unemployed increased from 14.5% in 1986to u).6% in 1988. There is, however, some difficulty in categorizing teenagers by occupation. Harris et a1 (2) reported that teenagers tended to be categorized by others as ‘home duties’ when they considered themselves as unemployed.
If, Hospital of delivery The distribution of teenage confinements by hospital of delivery was very different from that for confinements to women aged 20-29 years. A larger proportion of teenage confinements took place in metropolitan teaching hospitals (64.8% versus 50.3%) and country hospitals (32.5% versus 28.0%) compared with confinements of women in their twenties. Only 2.7% of teenage confinements occurred in metropolitan private hospitals, compared with 21.7% for the older women.
Figure 2. 1986-1988.
pqpancy
ram in South kunnlianCURB Regions
3. Obstetric Chamcteristics These are compared with those of women in their twenties in table 5 . (a) Fist pregnancy experience For 70.3Vo of the teenagers, this was their first pregnancy and for 23.2% the second. Of those who had had
’hbk 5. lkeaage ConfinclaccltrCompared r i t b Cooflrrmcntr of Women Aged 20-29 Yam, Sooth Amdnlh. 1906-1W l k n a g e women Women aged 2029 w a n Relative risk of characterink Chpnrctcristic (n = 3.483) (n = 11.740) (9% confidence limits)
(Mothers) Ram - Aboriginal Single marital status Private hospital delivery No pmious pregnancy Uncertain of LMP date Antenatal visits < 7 Medical condition Obstetric complication Induction of Labour Method of deliwry Spontaneous vaginal Emergency Caesarean Elective Caesartan Other (assisted) Labour or delivery complication
( I .9%) (13.01) (21.7%) (35.1%) (19.4%) (6.1%)* (7.7Qo) (24.8%) (22.6Qr)
4.05 4.47 0.12 2.00 1.94 2.67 1.62 1. I9 0.23
( I . 12.1.26) (0.20.0.27)
(68.2%) 7,594 (64.7%) (11.5%) 1.231 (10.5%) 137 (3.9%) 908 (7.7%) 569 (16.3Qo) 2,007 (17.1%) 1,240 (35.6%) 4,408 (37.51) (Babies) (n = 3.514) (N = ii,sai) Low birth-weight 328 (9.38) 130 (6.1 %) Gestational age
