Australian & New Zealand Journal of Obstetrics & Gynaecology, 2005
Objective: To determine the prevalence of self-reported substance use during pregnancy in South A... more Objective: To determine the prevalence of self-reported substance use during pregnancy in South Australia, the characteristics of substance users, their obstetric outcomes and the perinatal outcomes of their babies.Methods: Multivariable logistic regression with STATA statistical software was undertaken using the South Australian perinatal data collection 1998–2002. An audit was conducted on every fifth case coded as substance use to identify the actual substances used.Results: Substance use was reported by women in 707 of 89 080 confinements (0.8%). Marijuana (38.9%), methadone (29.9%), amphetamines (14.6%) and heroin (12.5%) were most commonly reported, with polydrug use among 18.8% of the women audited. Substance users were more likely than non-users to be smokers, to have a psychiatric condition, to be single, indigenous, of lower socio-economic status and living in the metropolitan area. The outcome models had poor predictive powers. Substance use was associated with increased risks for placental abruption (OR 2.53) and antepartum haemorrhage from other causes (OR 1.41). The exposed babies had increased risks for preterm birth (OR 2.63), small for gestational age (OR 1.79), congenital abnormalities (1.52), nursery stays longer than 7 days (OR 4.07), stillbirth (OR 2.54) and neonatal death (OR 2.92).Conclusions: Substance use in pregnancy is associated with increased risks for antepartum haemorrhage and poor perinatal outcomes. However, only a small amount of the variance in outcomes can be explained by the substance use alone. Recent initiatives to improve identification and support of women exposed to adverse health, psychosocial and lifestyle factors will need evaluation.
Archives of Disease in Childhood-fetal and Neonatal Edition, 1997
Aims-To identify perinatal risk factors for developmental dysplasia of the hip (DDH) and define t... more Aims-To identify perinatal risk factors for developmental dysplasia of the hip (DDH) and define the risk for each factor. Methods-In this case control study, using logistic regression analysis, all 1127 cases of isolated DDH live born in South Australia in 1986-93 and notified to the South Australian Birth Defects Register were included; controls comprised 150 130 live births in South Australia during the same period without any notified congenital abnormalities. Results-Breech presentation, oligohydramnios, female sex and primiparity were confirmed as risk factors for DDH. Significant findings were an increased risk for vaginal delivery over caesarean section for breech presentation (as well as an increased risk for emergency section over elective section), high birthweight (>4000 g), postmaturity and older maternal age; multiple births and preterm births had a reduced risk. There was no increased risk for caesarean section in the absence of breech presentation. For breech presentation, the risk of DDH was estimated to be at least 2.7% for girls and 0.8% for boys; a combination of factors increased the risk. Conclusions-It is suggested that the risk factors identified be used as indications for repeat screening at 6 weeks of age and whenever possible in infancy. Other indications are family history and associated abnormalities. (Arch Dis Child 1997;76:F94-F100)
Australian & New Zealand Journal of Obstetrics & Gynaecology, 2004
Background: There have been conflicting reports about pregnancy outcome in the hypertensive disor... more Background: There have been conflicting reports about pregnancy outcome in the hypertensive disorders of pregnancy. The present study was undertaken to examine outcomes using a population database.
Australian & New Zealand Journal of Obstetrics & Gynaecology, 2001
The objective of this study was to determine whether women who have experienced an unexplained st... more The objective of this study was to determine whether women who have experienced an unexplained stillbirth have a higher risk of adverse perinatal outcomes in subsequent births. We compared 316 subsequent births to women with a previous unexplained stillbirth, with 3160 births to women with no previous history of stillbirth, matched by year of birth, in the period 1987–1997, from the South Australian perinatal database, using logistic regression analysis. There was no increase in the rate of stillbirth and no statistically significant increase in the rate of perinatal death (OR 1.62 [95% CI 0.63^4.20]) or neonatal death, although larger studies are needed to confirm this. However, after adjusting for age, parity, and hospital category of birth, women who had a previous stillbirth had increased incidences in subsequent births of abnormal glucose tolerance or gestational diabetes (a fourfold increase); induction of labour and elective Caesarean section; fetal distress and postpartum haemorrhage; and forceps and emergency Caesarean delivery and preterm birth, which were independent of Induction of labour. Gestational age at birth and birthweight were also significantly reduced, suggesting a need for close monitoring of their future pregnancies.
Australian & New Zealand Journal of Obstetrics & Gynaecology, 1991
EDITORIAL COMMENT: Readers please note that this paper on teenage pregnancy has the unique qualit... more EDITORIAL COMMENT: Readers please note that this paper on teenage pregnancy has the unique quality of coming from the only Australian State in which it is a statutory requirement to notify all cases of termination of pregnancy. The authors have therefore been able to provide important information regarding the characteristics of pregnant teenagers and the changing incidence of abortion as well as the obstetric results in continuing pregnancies. These data allow deductions concerning teenage behaviour resulting in pregnancy. The results identify subgroups of our population who require special counselling and care. Hopefully the Council members of the Royal Australian College of Obstetricians and Gynaecologists will use their influence to encourage alt State Parliaments to introduce legislation requiring notification of all cases of termination of pregnancy. We need the facts to identify the high risk groups, so that available resources can be appropriately directed.Summary: Teenage pregnancies accounted for 6.0% of confinements and 24.8% of legal abortions in South Australia in 1986–1988. 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 or an elective Caesarean section. They had higher frequencies of preterm deliveries (8.9%) and low birth-weight babies (9.3%). 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.
American Journal of Obstetrics and Gynecology, 2003
OBJECTIVES: The purpose of this study was to determine the effect of maternal factors associated ... more OBJECTIVES: The purpose of this study was to determine the effect of maternal factors associated with impaired placental function on stillbirth and neonatal death rates in South Australia. STUDY DESIGN: From 1991 to 2000, the South Australian Pregnancy Outcome Unit's population database was searched to identify stillbirths and neonatal deaths in women with maternal medical conditions during pregnancy and in twin and singleton pregnancies. RESULTS: Women with hypertension and carbohydrate intolerance and who smoked during pregnancy had an increased risk of stillbirth. Women with twin pregnancies had a significantly higher stillbirth rate than for singletons at each week of gestational age. An increase in stillbirth rate at later gestations was seen with singletons, with a similar trend in twins but rising from 36 weeks' gestation. CONCLUSION: There is a clinical correlation between maternal factors associated with impaired placental function and increased risk of stillbirth, suggesting that intrauterine fetal death represents the mortality end point in a spectrum of intrauterine hypoxia. (Am J Obstet Gynecol 2003;189:1731-6.)
Bjog-an International Journal of Obstetrics and Gynaecology, 1998
Objectives To describe the impact of rubella immunisation on the incidence of rubella, congenital... more Objectives To describe the impact of rubella immunisation on the incidence of rubella, congenital rubella syndrome and rubella-related terminations of pregnancy in South Australia, and to identify factors associated with a re-emerging problem.Design and Methods A population-based descriptive study using data from South Australian notifications of disease, births and terminations of pregnancy, the rubella immunisation programme, antenatal rubella antibody screening and paediatric hospital case records.Setting South Australia (population 1.48 million people; 20,000 births per year).Main outcome measures Incidence of rubella (age-sex specific), congenital rubella syndrome and rubella-related terminations of pregnancy; antenatal rubella sero-positive rates; rubella immunisation uptake rates.Results Rubella notification rates in 1990–1996 were significantly higher for males than females for ages 15–34 years. There were five cases of congenital rubella syndrome notified in 1980–1996 compared with at least 20 confirmed or compatible cases in 1965–1979. Rubella-related terminations of pregnancy are now rare, with the last termination for maternal rubella being in 1993. The antenatal rubella sero-positive rate in 1995 was 96.7%, but was significantly lower among Asian women born overseas (78.6% among those 30 years or older). Vaccination uptake rates in schoolgirls decreased between 1990 and 1994 (91.2% to 86.9%).Conclusions Since the introduction of rubella immunisation, the incidence of rubella infection among women of reproductive age, and of rubella-related terminations, has fallen. Congenital rubella syndrome has not been notified since 1990 but its risk persists with a recent increase in rubella notifications, a fall in school immunisation rates, a relatively low antenatal sero-positive rate among older Asian women born overseas and the trend towards giving birth at older ages. Effective immunisation programmes must be maintained, particularly in schools and for young children and migrant women.
The purpose of this study was to determine the prevalence, clinical characteristics, prenatal dia... more The purpose of this study was to determine the prevalence, clinical characteristics, prenatal diagnosis and occurrence of other birth defects with abdominal wall defects in births and terminations of pregnancy in South Australia (SA) and Western Australia (WA) over the period 1980–90. Cases of gastroschisis, exomphalos, bladder exstrophy, cloacal exstrophy and body stalk anomaly were ascertained from the WA Birth Defects Registry (1980–90) and the SA Birth Defects Register (1986–90). The registers are comparable population-based data collections with information on livebirths and stillbirths of at least 400 g birthweight or 20 weeks’ gestation, and terminations of pregnancy for fetal abnormality. The prevalence of gastroschisis was 1.65/10 000 births (59 cases) and of exomphalos 2.90/10 000 births (104 cases). There was no significant difference in prevalence of exomphalos or gastroschisis between SA and WA for the years 1986–90. However, if data from WA for the years 1980–85 were included, SA had a significantly higher prevalence of exomphalos (prevalence ratio 1.71, confidence interval [CI] 1.16–2.55), although not of gastroschisis (prevalence ratio 1.35, CI 0.79–2.32). Exomphalos was significantly more common in mothers < 20 years (odds ratio [OR] 2.45, CI 1.22–4.86) and in mothers of 40 years or older (OR 5.65, CI 1.69–16.77). Gastroschisis was more common in younger mothers (OR 8.76, CI 4.02–19.32). Both exomphalos and gastroschisis were associated with low birthweight, prematurity, intrauterine growth retardation and caesarean section. The reason for the higher prevalence of exomphalos in SA than WA was not clear, but may be related to differences in prenatal diagnosis. The association between maternal age < 20 years and exomphalos raises the possibility of common factors in the aetiology of gastroschisis and exomphalos.
Australian & New Zealand Journal of Obstetrics & Gynaecology, 1995
Summary: The oral retinoids, isotretinoin and etretinate, are highly teratogenic drugs which have... more Summary: The oral retinoids, isotretinoin and etretinate, are highly teratogenic drugs which have been available in Australia since 1985 because of their unique effectiveness in severe cystic acne, psoriasis and other keratinization disorders. Only dermatologists can prescribe them, but in spite of strict guidelines by the manufacturers and the College of Dermatologists, exposed pregnancies have occurred. We attempted to determine the circumstances of exposure to these drugs for the 18 pregnancies terminated in South Australia in 1985–1993, using questionnaires to medical practitioners who notified the terminations under legislation. The main reason for their occurrence was the lack of compliance with the use of effective contraception by the women. In South Australia, some prescriptions of oral retinoids by unauthorized doctors have been dispensed during this period. Using statistics on prescriptions dispensed, an estimate was made of 1 termination of pregnancy for 319 courses of treatment for women with isotretinoin. Extension of guidelines for prescription and more detailed counselling in relation to the use of contraception are recommended. It is also suggested that doctors intending to recommend terminations obtain consent to discuss exposure with the dermatologists concerned, who may not be aware of the exposed pregnancy.
To evaluate a South Australian campaign to promote and implement knowledge that taking adequate f... more To evaluate a South Australian campaign to promote and implement knowledge that taking adequate folate/folic acid in the periconceptional period can reduce the risk of having a baby with a neural tube defect. The campaign, conducted in October 1994--August 1995, targeted women of reproductive age and health professionals. Evaluation was by computer-assisted telephone interviews undertaken by random dialling throughout the State before and after the campaign, and by self-administered questionnaires to health professionals and women in the postnatal period. Women of reproductive age and four groups of health professionals. Knowledge about folate, folate-rich foods and the periconceptional period; participation of health professionals in advising women about folate; use of periconceptional folic acid supplements; sales of folic acid tablets; and prevalence of neural tube defects. Significant increases in knowledge about folate followed the campaign. Health professionals and women in the postnatal period had higher initial levels of knowledge about folate, which also increased significantly. The proportions of women taking periconceptional folic acid supplements, and of health professionals advising women planning a pregnancy about folate, also increased significantly, and folic acid tablet sales doubled. Total prevalence of neural tube defects declined between 1966 and 1999 from a baseline of 2.0 per 1,000 births to 1.1 per 1,000 births (Poisson regression, P= 0.03; average decline of 1.0% per year). A short educational campaign with a limited budget ($40,000) can promote folate successfully, but alternative strategies such as food fortification are likely to be needed to achieve adequate periconceptional folate intake for a very high proportion of women.
Australian & New Zealand Journal of Obstetrics & Gynaecology, 2002
To compare pregnancy characteristics and outcomes between Aboriginal and non-Aboriginal teenagers... more To compare pregnancy characteristics and outcomes between Aboriginal and non-Aboriginal teenagers. DESIGN, SETTING AND POPULATION: A retrospective cohort study using the perinatal data collection for South Australian births in 1995-1999: 449 Aboriginal and 4,625 non-Aboriginal teenagers. Comparison of socio-demographic and clinical characteristics, using relative risks. Rates of pregnancy, smoking during pregnancy, induction, delivery method, preterm and small-for-gestational-age births and perinatal mortality Aboriginal teenagers have a pregnancy rate more than twice as high as non-Aboriginal, but a smaller proportion of pregnancies are terminated. They have pregnancies earlier, are more likely to be single, to smoke during pregnancy, to have few antenatal visits, to give birth in a country hospital and to have infections and anaemia. They have lower induction and analgesia rates, but a higher caesarean section rate. Their babies are more likely to be small-for-gestational-age and preterm, to have a congenital abnormality, to require special and intensive nursery care and stay longer in hospital. While their perinatal mortality rate has halved since a decade ago, their neonatal death rate is still twice that of non-Aboriginal births. Aboriginal teenagers need special attention. Support in particular is needed for Aboriginal health workers in preconceptional counselling and health promotion programs that build the capacity of the community, eg concerning proper nutrition during pregnancy, smoking cessation, breastfeeding, SIDS prevention, support for early and regular attendance for antenatal care in friendly and culturally appropriate environments. Outreach services and sexual health services for young Aboriginal people also need expansion.
Bjog-an International Journal of Obstetrics and Gynaecology, 1995
Objective To determine the sensitivity of antenatal screening methods for neural tube defects in ... more Objective To determine the sensitivity of antenatal screening methods for neural tube defects in population-based screening in South Australia in 1986–1991, and whether ultrasound can replace serum alpha-fetoprotein screening in terms of achieving an equivalent level of sensitivity.Design and setting Ascertainment of all births and terminations of pregnancy with neural tube defects from multiple sources for 1986–1991 in South Australia. Serum and amniotic fluid alpha-fetoprotein results were obtained from the only laboratory performing the tests as a Statewide antenatal screening programme, and information on ultrasound screening from case notifications, hospital case records and medical practitioners who cared for the women.Subjects All 243 births and terminations of pregnancy with neural tube defects in South Australia in 1986–1991.Main outcome measures The sensitivity of individual screening methods and of all methods used, particularly for spina bifida.Results For pregnancies with neural tube defects screened by any method (serum alpha-fetoprotein, ultrasound or amniocentesis), 86YO sensitivity was achieved. Ultrasound screening for anencephaly achieved 100 % sensitivity even in low risk pregnancies, compared with 92 % for serum alpha-fetoprotein. For spina bifida, the sensitivity of ultrasound screening increased with the level of risk in pregnancy: it was 60% in low risk pregnancies, which was equivalent to that of serum alpha-fetoprotein screening (64%); 89% in high risk pregnancies and 100% for women referred for confirmation of a suspected spina bifida by another ultrasonographer (×12 for trend = 23.49, P < 0.0001). Ultrasound screening in high risk pregnancies for spina bifida achieved higher sensitivity in teaching hospitals compared with other ultrasound services in the State (97%vs 65%), but sensitivity was equivalent for low risk pregnancies. It is estimated that, had the serum screening programme not been in place, the level of sensitivity achieved for spina bifida by ultrasound and amniocentesis would have been 62% compared with the actual situation of 76% with the programme in existence, a difference of nearly 15% (95% CI 2.5 to 267) (×12= 5.45, P= 0.02).Conclusions Antenatal screening for neural tube defects in South Australia achieved a higher level of sensitivity with the maternal serum alpha–fetoprotein programme in place. We conclude that the serum screening programme should continue in South Australia pending a significant improvement in the sensitivity of routine ultrasound screening for spina bifida.
Australian and New Zealand Journal of Public Health, 2008
Objectives:To describe trends in teenage pregnancy rates in South Australia and Australia in 1970... more Objectives:To describe trends in teenage pregnancy rates in South Australia and Australia in 1970–2000, and the socio-demographic and clinical characteristics and outcomes of teenage women who gave birth in South Australia in 1995–99.Methods:A descriptive study using population-based legislated South Australian perinatal and abortion data, Australian Medicare and hospital morbidity data on abortions, and birth registration rates from the Australian Bureau of Statistics.Results:The teenage pregnancy rate in South Australia fell in the 1970s and 1980s, increased in the 1990s, but is declining at the turn of the century. Teenage abortions exceeded livebirths annually from 1994, and in 2000 the teenage abortion, birth and pregnancy rates were 22.4, 18.3 and 40.8 per 1,000 respectively. The Australian rates, which are an underestimate, follow the South Australian trends and are declining but still much higher than in many western European countries. High socio-economic areas in South Australia have the lowest teenage pregnancy rates but the highest proportion of teenage pregnancies terminated. Teenagers who gave birth were more likely than older women to be Australian-born, Aboriginal, smokers during pregnancy (47% vs. 23%), to attend few antenatal visits, and to have preterm, small-for-gestational-age and low birthweight babies and neonatal deaths. Perinatal mortality has halved among teenagers under 17 years in the past decade.Conclusions and implications:Births to South Australian teenage women are associated with social disadvantage and relatively poor perinatal outcomes, although these have improved. Current strategies are aimed at reducing the incidence of unplanned teenage pregnancy and improving support for pregnant teenagers.
Bjog-an International Journal of Obstetrics and Gynaecology, 2000
Objectives To describe the impact of maternal serum screening on the birth prevalence of Down's s... more Objectives To describe the impact of maternal serum screening on the birth prevalence of Down's syndrome and on the use of amniocentesis and chorionic villus sampling in South Australia.Design A descriptive population-based study.Setting South Australia (population 1.48 million persons; approximately 20,000 births per year).Participants Women who had births or terminations of pregnancy with Down's syndrome in 1982–1996, women who had maternal serum screening in 1991–1996, amniocentesis or chorionic villus sampling in 1986–1996.Methods Analysis of data from multiple sources on maternal serum screening, amniocentesis and chorionic villus sampling, births and terminations of pregnancy.Main outcome measures Total prevalence and birth prevalence of Down's syndrome each year in 1982–1996; proportion of pregnant women using maternal serum screening in 1991–1996, and proportion using amniocentesis and chorionic villus sampling by indication in 1986–1996, by age group.Results Use of maternal serum screening for Down's syndrome increased from 17% when introduced in 1991 to 76% of women who gave birth in 1996. Between 1982 and 1986 and 1996, terminations of pregnancy for fetal Down's syndrome increased from 7.1% to 75% and the birth prevalence of Down's syndrome fell by 60% from 1.05 to 0.42 per 1,000 births, against the background of an increase in total prevalence due to increasing maternal age. The use of amniocentesis increased from 5.8% in 1991 to 10.1% in 1996 mainly due to the increase among women younger than 35 years with maternal serum screening as the main reason. The increasing chorionic villus sampling rate among younger women stabilised at 0.4%, while the rate among older women decreased from 11.0% to 7.4%.Conclusions The introduction of maternal serum screening in South Australia has resulted in increased use of any prenatal testing for Down's syndrome from about 7% (mainly older women having amniocentesis or chorionic villus sampling) to 84% of women (about 8% having direct amniocentesis or chorionic villus sampling and 76% having maternal serum screening first). This has resulted in a significant fall in the birth prevalence of Down's syndrome, maternal serum screening was the first indication of Down's syndrome for about half the terminations of pregnancy for Down's syndrome in 1993–1996, including three quarters of those in younger women.
Australian & New Zealand Journal of Obstetrics & Gynaecology, 2005
Objective: To determine the prevalence of self-reported substance use during pregnancy in South A... more Objective: To determine the prevalence of self-reported substance use during pregnancy in South Australia, the characteristics of substance users, their obstetric outcomes and the perinatal outcomes of their babies.Methods: Multivariable logistic regression with STATA statistical software was undertaken using the South Australian perinatal data collection 1998–2002. An audit was conducted on every fifth case coded as substance use to identify the actual substances used.Results: Substance use was reported by women in 707 of 89 080 confinements (0.8%). Marijuana (38.9%), methadone (29.9%), amphetamines (14.6%) and heroin (12.5%) were most commonly reported, with polydrug use among 18.8% of the women audited. Substance users were more likely than non-users to be smokers, to have a psychiatric condition, to be single, indigenous, of lower socio-economic status and living in the metropolitan area. The outcome models had poor predictive powers. Substance use was associated with increased risks for placental abruption (OR 2.53) and antepartum haemorrhage from other causes (OR 1.41). The exposed babies had increased risks for preterm birth (OR 2.63), small for gestational age (OR 1.79), congenital abnormalities (1.52), nursery stays longer than 7 days (OR 4.07), stillbirth (OR 2.54) and neonatal death (OR 2.92).Conclusions: Substance use in pregnancy is associated with increased risks for antepartum haemorrhage and poor perinatal outcomes. However, only a small amount of the variance in outcomes can be explained by the substance use alone. Recent initiatives to improve identification and support of women exposed to adverse health, psychosocial and lifestyle factors will need evaluation.
Archives of Disease in Childhood-fetal and Neonatal Edition, 1997
Aims-To identify perinatal risk factors for developmental dysplasia of the hip (DDH) and define t... more Aims-To identify perinatal risk factors for developmental dysplasia of the hip (DDH) and define the risk for each factor. Methods-In this case control study, using logistic regression analysis, all 1127 cases of isolated DDH live born in South Australia in 1986-93 and notified to the South Australian Birth Defects Register were included; controls comprised 150 130 live births in South Australia during the same period without any notified congenital abnormalities. Results-Breech presentation, oligohydramnios, female sex and primiparity were confirmed as risk factors for DDH. Significant findings were an increased risk for vaginal delivery over caesarean section for breech presentation (as well as an increased risk for emergency section over elective section), high birthweight (>4000 g), postmaturity and older maternal age; multiple births and preterm births had a reduced risk. There was no increased risk for caesarean section in the absence of breech presentation. For breech presentation, the risk of DDH was estimated to be at least 2.7% for girls and 0.8% for boys; a combination of factors increased the risk. Conclusions-It is suggested that the risk factors identified be used as indications for repeat screening at 6 weeks of age and whenever possible in infancy. Other indications are family history and associated abnormalities. (Arch Dis Child 1997;76:F94-F100)
Australian & New Zealand Journal of Obstetrics & Gynaecology, 2004
Background: There have been conflicting reports about pregnancy outcome in the hypertensive disor... more Background: There have been conflicting reports about pregnancy outcome in the hypertensive disorders of pregnancy. The present study was undertaken to examine outcomes using a population database.
Australian & New Zealand Journal of Obstetrics & Gynaecology, 2001
The objective of this study was to determine whether women who have experienced an unexplained st... more The objective of this study was to determine whether women who have experienced an unexplained stillbirth have a higher risk of adverse perinatal outcomes in subsequent births. We compared 316 subsequent births to women with a previous unexplained stillbirth, with 3160 births to women with no previous history of stillbirth, matched by year of birth, in the period 1987–1997, from the South Australian perinatal database, using logistic regression analysis. There was no increase in the rate of stillbirth and no statistically significant increase in the rate of perinatal death (OR 1.62 [95% CI 0.63^4.20]) or neonatal death, although larger studies are needed to confirm this. However, after adjusting for age, parity, and hospital category of birth, women who had a previous stillbirth had increased incidences in subsequent births of abnormal glucose tolerance or gestational diabetes (a fourfold increase); induction of labour and elective Caesarean section; fetal distress and postpartum haemorrhage; and forceps and emergency Caesarean delivery and preterm birth, which were independent of Induction of labour. Gestational age at birth and birthweight were also significantly reduced, suggesting a need for close monitoring of their future pregnancies.
Australian & New Zealand Journal of Obstetrics & Gynaecology, 1991
EDITORIAL COMMENT: Readers please note that this paper on teenage pregnancy has the unique qualit... more EDITORIAL COMMENT: Readers please note that this paper on teenage pregnancy has the unique quality of coming from the only Australian State in which it is a statutory requirement to notify all cases of termination of pregnancy. The authors have therefore been able to provide important information regarding the characteristics of pregnant teenagers and the changing incidence of abortion as well as the obstetric results in continuing pregnancies. These data allow deductions concerning teenage behaviour resulting in pregnancy. The results identify subgroups of our population who require special counselling and care. Hopefully the Council members of the Royal Australian College of Obstetricians and Gynaecologists will use their influence to encourage alt State Parliaments to introduce legislation requiring notification of all cases of termination of pregnancy. We need the facts to identify the high risk groups, so that available resources can be appropriately directed.Summary: Teenage pregnancies accounted for 6.0% of confinements and 24.8% of legal abortions in South Australia in 1986–1988. 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 or an elective Caesarean section. They had higher frequencies of preterm deliveries (8.9%) and low birth-weight babies (9.3%). 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.
American Journal of Obstetrics and Gynecology, 2003
OBJECTIVES: The purpose of this study was to determine the effect of maternal factors associated ... more OBJECTIVES: The purpose of this study was to determine the effect of maternal factors associated with impaired placental function on stillbirth and neonatal death rates in South Australia. STUDY DESIGN: From 1991 to 2000, the South Australian Pregnancy Outcome Unit's population database was searched to identify stillbirths and neonatal deaths in women with maternal medical conditions during pregnancy and in twin and singleton pregnancies. RESULTS: Women with hypertension and carbohydrate intolerance and who smoked during pregnancy had an increased risk of stillbirth. Women with twin pregnancies had a significantly higher stillbirth rate than for singletons at each week of gestational age. An increase in stillbirth rate at later gestations was seen with singletons, with a similar trend in twins but rising from 36 weeks' gestation. CONCLUSION: There is a clinical correlation between maternal factors associated with impaired placental function and increased risk of stillbirth, suggesting that intrauterine fetal death represents the mortality end point in a spectrum of intrauterine hypoxia. (Am J Obstet Gynecol 2003;189:1731-6.)
Bjog-an International Journal of Obstetrics and Gynaecology, 1998
Objectives To describe the impact of rubella immunisation on the incidence of rubella, congenital... more Objectives To describe the impact of rubella immunisation on the incidence of rubella, congenital rubella syndrome and rubella-related terminations of pregnancy in South Australia, and to identify factors associated with a re-emerging problem.Design and Methods A population-based descriptive study using data from South Australian notifications of disease, births and terminations of pregnancy, the rubella immunisation programme, antenatal rubella antibody screening and paediatric hospital case records.Setting South Australia (population 1.48 million people; 20,000 births per year).Main outcome measures Incidence of rubella (age-sex specific), congenital rubella syndrome and rubella-related terminations of pregnancy; antenatal rubella sero-positive rates; rubella immunisation uptake rates.Results Rubella notification rates in 1990–1996 were significantly higher for males than females for ages 15–34 years. There were five cases of congenital rubella syndrome notified in 1980–1996 compared with at least 20 confirmed or compatible cases in 1965–1979. Rubella-related terminations of pregnancy are now rare, with the last termination for maternal rubella being in 1993. The antenatal rubella sero-positive rate in 1995 was 96.7%, but was significantly lower among Asian women born overseas (78.6% among those 30 years or older). Vaccination uptake rates in schoolgirls decreased between 1990 and 1994 (91.2% to 86.9%).Conclusions Since the introduction of rubella immunisation, the incidence of rubella infection among women of reproductive age, and of rubella-related terminations, has fallen. Congenital rubella syndrome has not been notified since 1990 but its risk persists with a recent increase in rubella notifications, a fall in school immunisation rates, a relatively low antenatal sero-positive rate among older Asian women born overseas and the trend towards giving birth at older ages. Effective immunisation programmes must be maintained, particularly in schools and for young children and migrant women.
The purpose of this study was to determine the prevalence, clinical characteristics, prenatal dia... more The purpose of this study was to determine the prevalence, clinical characteristics, prenatal diagnosis and occurrence of other birth defects with abdominal wall defects in births and terminations of pregnancy in South Australia (SA) and Western Australia (WA) over the period 1980–90. Cases of gastroschisis, exomphalos, bladder exstrophy, cloacal exstrophy and body stalk anomaly were ascertained from the WA Birth Defects Registry (1980–90) and the SA Birth Defects Register (1986–90). The registers are comparable population-based data collections with information on livebirths and stillbirths of at least 400 g birthweight or 20 weeks’ gestation, and terminations of pregnancy for fetal abnormality. The prevalence of gastroschisis was 1.65/10 000 births (59 cases) and of exomphalos 2.90/10 000 births (104 cases). There was no significant difference in prevalence of exomphalos or gastroschisis between SA and WA for the years 1986–90. However, if data from WA for the years 1980–85 were included, SA had a significantly higher prevalence of exomphalos (prevalence ratio 1.71, confidence interval [CI] 1.16–2.55), although not of gastroschisis (prevalence ratio 1.35, CI 0.79–2.32). Exomphalos was significantly more common in mothers < 20 years (odds ratio [OR] 2.45, CI 1.22–4.86) and in mothers of 40 years or older (OR 5.65, CI 1.69–16.77). Gastroschisis was more common in younger mothers (OR 8.76, CI 4.02–19.32). Both exomphalos and gastroschisis were associated with low birthweight, prematurity, intrauterine growth retardation and caesarean section. The reason for the higher prevalence of exomphalos in SA than WA was not clear, but may be related to differences in prenatal diagnosis. The association between maternal age < 20 years and exomphalos raises the possibility of common factors in the aetiology of gastroschisis and exomphalos.
Australian & New Zealand Journal of Obstetrics & Gynaecology, 1995
Summary: The oral retinoids, isotretinoin and etretinate, are highly teratogenic drugs which have... more Summary: The oral retinoids, isotretinoin and etretinate, are highly teratogenic drugs which have been available in Australia since 1985 because of their unique effectiveness in severe cystic acne, psoriasis and other keratinization disorders. Only dermatologists can prescribe them, but in spite of strict guidelines by the manufacturers and the College of Dermatologists, exposed pregnancies have occurred. We attempted to determine the circumstances of exposure to these drugs for the 18 pregnancies terminated in South Australia in 1985–1993, using questionnaires to medical practitioners who notified the terminations under legislation. The main reason for their occurrence was the lack of compliance with the use of effective contraception by the women. In South Australia, some prescriptions of oral retinoids by unauthorized doctors have been dispensed during this period. Using statistics on prescriptions dispensed, an estimate was made of 1 termination of pregnancy for 319 courses of treatment for women with isotretinoin. Extension of guidelines for prescription and more detailed counselling in relation to the use of contraception are recommended. It is also suggested that doctors intending to recommend terminations obtain consent to discuss exposure with the dermatologists concerned, who may not be aware of the exposed pregnancy.
To evaluate a South Australian campaign to promote and implement knowledge that taking adequate f... more To evaluate a South Australian campaign to promote and implement knowledge that taking adequate folate/folic acid in the periconceptional period can reduce the risk of having a baby with a neural tube defect. The campaign, conducted in October 1994--August 1995, targeted women of reproductive age and health professionals. Evaluation was by computer-assisted telephone interviews undertaken by random dialling throughout the State before and after the campaign, and by self-administered questionnaires to health professionals and women in the postnatal period. Women of reproductive age and four groups of health professionals. Knowledge about folate, folate-rich foods and the periconceptional period; participation of health professionals in advising women about folate; use of periconceptional folic acid supplements; sales of folic acid tablets; and prevalence of neural tube defects. Significant increases in knowledge about folate followed the campaign. Health professionals and women in the postnatal period had higher initial levels of knowledge about folate, which also increased significantly. The proportions of women taking periconceptional folic acid supplements, and of health professionals advising women planning a pregnancy about folate, also increased significantly, and folic acid tablet sales doubled. Total prevalence of neural tube defects declined between 1966 and 1999 from a baseline of 2.0 per 1,000 births to 1.1 per 1,000 births (Poisson regression, P= 0.03; average decline of 1.0% per year). A short educational campaign with a limited budget ($40,000) can promote folate successfully, but alternative strategies such as food fortification are likely to be needed to achieve adequate periconceptional folate intake for a very high proportion of women.
Australian & New Zealand Journal of Obstetrics & Gynaecology, 2002
To compare pregnancy characteristics and outcomes between Aboriginal and non-Aboriginal teenagers... more To compare pregnancy characteristics and outcomes between Aboriginal and non-Aboriginal teenagers. DESIGN, SETTING AND POPULATION: A retrospective cohort study using the perinatal data collection for South Australian births in 1995-1999: 449 Aboriginal and 4,625 non-Aboriginal teenagers. Comparison of socio-demographic and clinical characteristics, using relative risks. Rates of pregnancy, smoking during pregnancy, induction, delivery method, preterm and small-for-gestational-age births and perinatal mortality Aboriginal teenagers have a pregnancy rate more than twice as high as non-Aboriginal, but a smaller proportion of pregnancies are terminated. They have pregnancies earlier, are more likely to be single, to smoke during pregnancy, to have few antenatal visits, to give birth in a country hospital and to have infections and anaemia. They have lower induction and analgesia rates, but a higher caesarean section rate. Their babies are more likely to be small-for-gestational-age and preterm, to have a congenital abnormality, to require special and intensive nursery care and stay longer in hospital. While their perinatal mortality rate has halved since a decade ago, their neonatal death rate is still twice that of non-Aboriginal births. Aboriginal teenagers need special attention. Support in particular is needed for Aboriginal health workers in preconceptional counselling and health promotion programs that build the capacity of the community, eg concerning proper nutrition during pregnancy, smoking cessation, breastfeeding, SIDS prevention, support for early and regular attendance for antenatal care in friendly and culturally appropriate environments. Outreach services and sexual health services for young Aboriginal people also need expansion.
Bjog-an International Journal of Obstetrics and Gynaecology, 1995
Objective To determine the sensitivity of antenatal screening methods for neural tube defects in ... more Objective To determine the sensitivity of antenatal screening methods for neural tube defects in population-based screening in South Australia in 1986–1991, and whether ultrasound can replace serum alpha-fetoprotein screening in terms of achieving an equivalent level of sensitivity.Design and setting Ascertainment of all births and terminations of pregnancy with neural tube defects from multiple sources for 1986–1991 in South Australia. Serum and amniotic fluid alpha-fetoprotein results were obtained from the only laboratory performing the tests as a Statewide antenatal screening programme, and information on ultrasound screening from case notifications, hospital case records and medical practitioners who cared for the women.Subjects All 243 births and terminations of pregnancy with neural tube defects in South Australia in 1986–1991.Main outcome measures The sensitivity of individual screening methods and of all methods used, particularly for spina bifida.Results For pregnancies with neural tube defects screened by any method (serum alpha-fetoprotein, ultrasound or amniocentesis), 86YO sensitivity was achieved. Ultrasound screening for anencephaly achieved 100 % sensitivity even in low risk pregnancies, compared with 92 % for serum alpha-fetoprotein. For spina bifida, the sensitivity of ultrasound screening increased with the level of risk in pregnancy: it was 60% in low risk pregnancies, which was equivalent to that of serum alpha-fetoprotein screening (64%); 89% in high risk pregnancies and 100% for women referred for confirmation of a suspected spina bifida by another ultrasonographer (×12 for trend = 23.49, P < 0.0001). Ultrasound screening in high risk pregnancies for spina bifida achieved higher sensitivity in teaching hospitals compared with other ultrasound services in the State (97%vs 65%), but sensitivity was equivalent for low risk pregnancies. It is estimated that, had the serum screening programme not been in place, the level of sensitivity achieved for spina bifida by ultrasound and amniocentesis would have been 62% compared with the actual situation of 76% with the programme in existence, a difference of nearly 15% (95% CI 2.5 to 267) (×12= 5.45, P= 0.02).Conclusions Antenatal screening for neural tube defects in South Australia achieved a higher level of sensitivity with the maternal serum alpha–fetoprotein programme in place. We conclude that the serum screening programme should continue in South Australia pending a significant improvement in the sensitivity of routine ultrasound screening for spina bifida.
Australian and New Zealand Journal of Public Health, 2008
Objectives:To describe trends in teenage pregnancy rates in South Australia and Australia in 1970... more Objectives:To describe trends in teenage pregnancy rates in South Australia and Australia in 1970–2000, and the socio-demographic and clinical characteristics and outcomes of teenage women who gave birth in South Australia in 1995–99.Methods:A descriptive study using population-based legislated South Australian perinatal and abortion data, Australian Medicare and hospital morbidity data on abortions, and birth registration rates from the Australian Bureau of Statistics.Results:The teenage pregnancy rate in South Australia fell in the 1970s and 1980s, increased in the 1990s, but is declining at the turn of the century. Teenage abortions exceeded livebirths annually from 1994, and in 2000 the teenage abortion, birth and pregnancy rates were 22.4, 18.3 and 40.8 per 1,000 respectively. The Australian rates, which are an underestimate, follow the South Australian trends and are declining but still much higher than in many western European countries. High socio-economic areas in South Australia have the lowest teenage pregnancy rates but the highest proportion of teenage pregnancies terminated. Teenagers who gave birth were more likely than older women to be Australian-born, Aboriginal, smokers during pregnancy (47% vs. 23%), to attend few antenatal visits, and to have preterm, small-for-gestational-age and low birthweight babies and neonatal deaths. Perinatal mortality has halved among teenagers under 17 years in the past decade.Conclusions and implications:Births to South Australian teenage women are associated with social disadvantage and relatively poor perinatal outcomes, although these have improved. Current strategies are aimed at reducing the incidence of unplanned teenage pregnancy and improving support for pregnant teenagers.
Bjog-an International Journal of Obstetrics and Gynaecology, 2000
Objectives To describe the impact of maternal serum screening on the birth prevalence of Down's s... more Objectives To describe the impact of maternal serum screening on the birth prevalence of Down's syndrome and on the use of amniocentesis and chorionic villus sampling in South Australia.Design A descriptive population-based study.Setting South Australia (population 1.48 million persons; approximately 20,000 births per year).Participants Women who had births or terminations of pregnancy with Down's syndrome in 1982–1996, women who had maternal serum screening in 1991–1996, amniocentesis or chorionic villus sampling in 1986–1996.Methods Analysis of data from multiple sources on maternal serum screening, amniocentesis and chorionic villus sampling, births and terminations of pregnancy.Main outcome measures Total prevalence and birth prevalence of Down's syndrome each year in 1982–1996; proportion of pregnant women using maternal serum screening in 1991–1996, and proportion using amniocentesis and chorionic villus sampling by indication in 1986–1996, by age group.Results Use of maternal serum screening for Down's syndrome increased from 17% when introduced in 1991 to 76% of women who gave birth in 1996. Between 1982 and 1986 and 1996, terminations of pregnancy for fetal Down's syndrome increased from 7.1% to 75% and the birth prevalence of Down's syndrome fell by 60% from 1.05 to 0.42 per 1,000 births, against the background of an increase in total prevalence due to increasing maternal age. The use of amniocentesis increased from 5.8% in 1991 to 10.1% in 1996 mainly due to the increase among women younger than 35 years with maternal serum screening as the main reason. The increasing chorionic villus sampling rate among younger women stabilised at 0.4%, while the rate among older women decreased from 11.0% to 7.4%.Conclusions The introduction of maternal serum screening in South Australia has resulted in increased use of any prenatal testing for Down's syndrome from about 7% (mainly older women having amniocentesis or chorionic villus sampling) to 84% of women (about 8% having direct amniocentesis or chorionic villus sampling and 76% having maternal serum screening first). This has resulted in a significant fall in the birth prevalence of Down's syndrome, maternal serum screening was the first indication of Down's syndrome for about half the terminations of pregnancy for Down's syndrome in 1993–1996, including three quarters of those in younger women.
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