Ear disease and hearing loss: a descriptive study of Aboriginal children living in metropolitan South Australia.

OBJECTIVE: This article aims to describe the rates of middle ear disease in Aboriginal children living in metropolitan Adelaide. METHODS: Data from the Under 8s Ear Health Program (population-based outreach screening) were analysed to identify rates of ear disease and the referral outcomes for children identified with ear conditions during screening. RESULTS: In total, 1598 children participated in at least one screening between May 2013 and May 2017. Males and females were equally represented; 73.2% had one or more abnormal findings on otoscopy at the first screening visit, 42% had abnormal tympanometry, and 20% registered a "fail" on otoacoustic emission testing. The referral pathway for children with abnormal findings included referrals to their GP, Audiology, and Ear Nose Throat (ENT) Departments. Also, 35% (562/1598) of the children screened required referral either to a GP or Audiology, and 28% of those referred (158/562) or 9.8% (158/1598) of the total number of children screened required further ENT management. CONCLUSIONS: High rates of ear disease and hearing problems in urban Aboriginal children were detected in this study. Existing social, environmental, and clinical interventions need to be evaluated. Closer monitoring including data linkage may assist to better understand the effectiveness, timeliness, and challenges of public health interventions and follow-up clinical services to a population-based screening program. IMPLICATIONS FOR PUBLIC HEALTH: Aboriginal-led population-based outreach programs such as the Under 8s Ear Health Program augmented by seamless integration with education, allied health and tertiary health services should be prioritised for expansion and continued funding.

The Spectrum of Adverse Pregnancy Outcomes Based on Kidney Disease Diagnoses: A 20-Year Population Study.

BACKGROUND AND OBJECTIVES: Kidney disorders in pregnancy may be under-recognized and have variable impact on outcomes depending on diagnosis. Population-level data are limited, particularly for Australia, and comparison of impact of different kidney disorders on pregnancy has rarely been assessed. This study examined the prevalence and outcomes of varied kidney disorders using population-level perinatal data from a large cohort. METHODS: Women with singleton pregnancies > 20 weeks' gestation from the South Australian Pregnancy Outcomes Unit (1990-2012). Women with a kidney disorders diagnostic code were grouped into categories (immunological, cystic/genetic, urological, vesicoureteral reflux (VUR), pyelonephritis and "other"). Key pregnancy outcomes were assessed, with adjustment for demographic variables. RESULTS: Kidney disorders were reported in 1,392 (0.3%) of 407,580 births. These pregnancies had increased risk of pregnancy-induced hypertension (OR 2.16, 95% CI 1.82-2.56), induction of labor (RRR vs. spontaneous birth 2.10, 95% CI 1.87-2.36), all Caesarean section (OR 1.31, 95% CI 1.17-1.47) as well as Caesarean section without labor (RRR 1.82, 95% CI 1.57-2.10), preterm birth (< 37 weeks; 2.76, 95% CI 2.40-3.18), low birth weight (< 2,500 g) infants (OR 2.43, 95% CI 2.07-2.84), and neonatal intensive care admission (OR 2.64, 95% CI 2.12-3.29). Diagnostic subgroups demonstrated differing patterns of adverse outcomes, enabling the development of a matrix of risk. Women with immunological renal conditions and VUR had greatest risk overall, and only women with immunological diseases had increased risk of small-for-gestational age < 10th centile (OR 2.36, 95% CI 1.26-4.42). Women with nonchronic urological conditions and pyelonephritis had increased risk of preterm birth, but not other adverse events. VUR conferred particularly increased risk of Caesarean section and induced labor. CONCLUSIONS: In a cohort of > 1,300 women with varied kidney disorders, increased adverse obstetric and perinatal events were observed, and the nature and magnitude of risk differed according to diagnosis. In particular, vesicoureteric reflux is not a benign condition in pregnancy. Women with nonchronic conditions still had increased risk of preterm birth. We confirm that women with kidney disorders warrant vigilant and tailored prepregnancy care and clinical care in pregnancy.

Human papillomavirus infection and intrauterine growth restriction: a data-linkage study.

OBJECTIVE: Using unbiased population data, to examine whether having a positive Pap smear, and thus a high probability of Human Papilloma Virus (HPV) infection, is a significant risk factor for intrauterine growth restriction (IUGR) in a subsequent pregnancy. STUDY DESIGN AND METHODS: Two independent population-based databases, namely the South Australian Perinatal Statistics Collection and the South Australian Cervical Screening Database, were deidentified and linked by the SANT Datalinkage Service. Analyses were performed on cases where Pap smear screening data was available for up to 2 years prior to a singleton live birth. Population characteristics and pregnancy related data were compared statistically by normal birth weight versus IUGR (10th percentile - known as small for gestational age (SGA), small for gestational age) and (3rd percentile birth weight - known as VLBW, very low birth weight). The association between cervical screening results and IUGR was assessed using generalized linear log binomial regression models. RESULTS: A total of 31,827 women met the criteria. Of these, 1311 women (4.1%) had a positive Pap smear within 2 years of the current pregnancy. Those having a positive Pap smear were more likely to have a baby with IUGR than those with negative smear results. For SGA, 5.8% babies were from mothers with positive Pap smears compared to 4.0% with negative smears indicating a 40% higher risk of having an SGA baby (95%CI 20-70%) among women with positive Pap smears. For VLBW, 7.6% mothers had positive Pap smears compared with 4.0% with negative smears (p < .001), which reflects a 90% increased risk (95%CI 40-150%). These associations reduced to 20% (95%CI 1-40%) and 50% (95%CI 10-100%) for SGA and VLBW, respectively, after adjusting for all other significant covariates including maternal age, ethnicity, marital status, occupation, smoking, pregnancy history, and maternal health during pregnancy. CONCLUSIONS: Mothers with a positive Pap smear have an increased risk of IUGR, especially for VLBW, which is independent of other risk factors. The results confirm previous findings in a small study and emphasise the need to consider the risks of both cancer and IUGR in all HPV vaccination programs.

Results of the first recorded evaluation of a national gestational diabetes mellitus register: Challenges in screening, registration, and follow-up for diabetes risk.

OBJECTIVE: Gestational Diabetes Mellitus (GDM) increases the risk of type 2 diabetes. A register can be used to follow-up high risk women for early intervention to prevent progression to type 2 diabetes. We evaluate the performance of the world's first national gestational diabetes register. RESEARCH DESIGN AND METHODS: Observational study that used data linkage to merge: (1) pathology data from the Australian states of Victoria (VIC) and South Australia (SA); (2) birth records from the Consultative Council on Obstetric and Paediatric Mortality and Morbidity (CCOPMM, VIC) and the South Australian Perinatal Statistics Collection (SAPSC, SA); (3) GDM and type 2 diabetes register data from the National Gestational Diabetes Register (NGDR). All pregnancies registered on CCOPMM and SAPSC for 2012 and 2013 were included-other data back to 2008 were used to support the analyses. Rates of screening for GDM, rates of registration on the NGDR, and rates of follow-up laboratory screening for type 2 diabetes are reported. RESULTS: Estimated GDM screening rates were 86% in SA and 97% in VIC. Rates of registration on the NGDR ranged from 73% in SA (2013) to 91% in VIC (2013). During the study period rates of screening at six weeks postpartum ranged from 43% in SA (2012) to 58% in VIC (2013). There was little evidence of recall letters resulting in screening 12 months follow-up. CONCLUSIONS: GDM Screening and NGDR registration was effective in Australia. Recall by mail-out to young mothers and their GP's for type 2 diabetes follow-up testing proved ineffective.

Seasonality of hypertensive disorders of pregnancy - A South Australian population study.

OBJECTIVES: To investigate the seasonal variation of hypertensive disorders of pregnancy (HDP) in South Australia. STUDY DESIGN: Retrospective population study including all 107,846 liveborn singletons during 2007-2014 in South Australia. Seasonality in incidence of HDP in relation to estimated date of conception (eDoC) and date of birth (DoB) were examined using Fourier series analysis. MAIN OUTCOME MEASURES: Seasonality of HDP in relation to eDoC and DoB. RESULTS: During 2007-2014, the incidence of HDP was 7.1% (n = 7,612). Seasonal modeling showed a strong relationship between HDP and eDoC (p < .001) and DoB (p < .001). Unadjusted and adjusted models (adjusted for maternal age, body mass index, ethnicity, parity, type of health care, smoking and gestational diabetes mellitus) demonstrated the presence of a peak incidence (7.8%, 7.9% respectively) occurring among pregnancies with eDoC in late Spring (November) and a trough (6.4% and 6.3% respectively) among pregnancies with eDoC in late Autumn (May). Both unadjusted and adjusted seasonal modelling showed a peak incidence of HDP for pregnancies with DoB in August (8.0%, 8.1% respectively) and a nadir among pregnancies with eDoB in February (6.2%). CONCLUSION: The highest incidence of HDP was associated with pregnancies with eDoC during late spring and summer and birth in winter, while the lowest incidence of HDP was associated with pregnancies with eDoC during late autumn and early winter and birth in summer. Nutrient intake, in particular vitamin D, sunlight exposure and physical activity may affect maternal, fetal and placental adaptation to pregnancy and are potential contributors to the seasonal variation of HDP.

Long-term Trends in Singleton Preterm Birth in South Australia From 1986 to 2014.

OBJECTIVE: To describe long-term trends in the prevalence of preterm birth and rates of preterm birth in singleton pregnancies complicated by hypertensive disorders of pregnancy, small for gestational age (SGA), and preterm prelabor rupture of membranes (PROM) in South Australia. METHODS: We conducted a retrospective population study including all singleton live births in the state of South Australia from 1986 to 2014. Long-term trends for preterm birth, hypertensive disorders of pregnancy, SGA, preterm PROM as well as stillbirth were assessed using joinpoint regression analyses. Trends in maternal age, body mass index (BMI), ethnic diversity, parity, and smoking over time were also assessed. RESULTS: From 1986 to 2014, with a total of 539,234 singleton births, the overall preterm birth rates increased from 5.1% to 7.1% (P<.001) and for iatrogenic preterm birth increased from 1.6% to 3.2% (P<.001). The incidence of hypertensive disorders of pregnancy decreased from 8.7% to 7.2%. Among pregnancies complicated by hypertensive disorders of pregnancy, the proportion of preterm birth increased (10.4-17.5%, P<.001). The incidence of SGA decreased from 11.1% to 8.0%. Among pregnancies complicated by SGA, the proportion of preterm birth increased (2.9-5.4%, P<.001). The incidence of preterm PROM increased from 1.4% to 2.2%. Among pregnancies complicated by preterm PROM, the proportion of preterm birth remained stable. Preterm stillbirth rates declined (4.23-2.32%, P<.001). Maternal age, BMI, and ethnic diversity have all increased since 1986, whereas maternal smoking has decreased. CONCLUSION: In South Australia, the preterm birth rate among singletons increased from 1986 to 2014 by 40%, with iatrogenic preterm birth being responsible for 80% of this increase. Incidence of hypertensive disorders of pregnancy and SGA declined. Among pregnancies complicated by hypertensive disorders of pregnancy and SGA, the proportions of preterm birth increased, indicating earlier interventions in these women. The diagnosis of preterm PROM increased from 1% to 2%, and greater than 80% of preterm PROM was associated with preterm birth after 1990. Increasing iatrogenic delivery may be attributable, in part, to changing maternal phenotype and to altered clinicians' behavior. However, improvements in fetal surveillance, particularly ultrasonography, and advanced neonatal care may underpin perinatal clinical decision-making and the likelihood of iatrogenic birth.

A retrospective cohort review of intrahepatic cholestasis of pregnancy in a South Australian population.

OBJECTIVE: To review the management and outcomes of Intrahepatic Cholestasis of Pregnancy (ICP) in South Australia (SA) over the past decade. DESIGN: Retrospective cohort review. SETTING: Public clinics at two teaching hospitals in SA. POPULATION: All pregnancies associated with ICP (defined as pruritus with serum bile acids≥10µmol/L) managed 2001-2010. METHODS: Identification of subjects (laboratory database), detailed chart-review to ascertain demographics, maternal/perinatal outcomes and associated pregnancy comorbidities, analysis of mild/severe disease cohorts, comparison with normal population data, using Student's t-test or Mann-Whitney U test as appropriate for continuous variables, and Pearson's chi-square test or Fisher's exact test for categorical variables. Unadjusted odds ratios (OR) with 95% confidence intervals (95% CI) were calculated in comparison with the general pregnant population for clinically significant outcomes. RESULTS: 320 women (359 pregnancies) were diagnosed with ICP over the 10-years: incidence 0.6%/year. Within the cohort, the incidences of gestational diabetes (12.5%; OR 3.06, 95% CI 2.23-4.18), pre-eclampsia (10.3%; OR 75.84, 95% CI 52.91-178.70), and spontaneous preterm labour (23.1%; OR 2.05, 95% CI 1.41-2.98) were much higher than in the general SA pregnant population. Pregnancies with severe ICP (serum bile acids≥40µmol/L) had ICP diagnosed earlier (231 vs 248 days, P<0.001), and ended earlier (256 vs 260 days, P<0.001) with lower birthweights (2827g vs 3093g, P <0.001) than those with mild ICP. Neonates of severe ICP mothers were more likely to require special-care-nursery admission, but perinatal complication rates did not differ. There were no stillbirths. CONCLUSION: This large Australian retrospective cohort study confirms generally favourable outcomes associated with ICP, mild or severe, with no stillbirths, likely secondary to proactive medical management. A high proportion of pregnancies were also affected by gestational diabetes, pre-eclampsia, and/or spontaneous pre-term labour compared with the general population.

Sperm donation perinatal outcomes in an Australian population cohort.

AIM: To compare perinatal outcomes for neonates conceived with donated sperm with those for neonates conceived spontaneously in an Australian population cohort. METHODS: Perinatal outcomes for all births in South Australia for the period January 1986-December 2002 were linked with assisted reproductive treatment records to determine those conceived from donated sperm. Birth outcome measures were analyzed using Student's t-test and logistic regression using generalized estimating equations to determine statistical significance. RESULTS: Donor sperm neonates were not significantly different from their spontaneously conceived counterparts in terms of mean birthweight, low birthweight, preterm delivery, small for gestational age, or large for gestational age. They were, however, significantly more likely to be born at lower mean gestational age (P = 0.012), and to have preterm delivery with low birthweight (P = 0.008), when controlling for maternal age, parity, ethnicity, socioeconomic quartile and baby's sex. These associations were not apparent when singletons and twins were considered separately. CONCLUSION: There was some evidence of compromised perinatal outcomes for donor sperm neonates compared with their spontaneously conceived counterparts, which appeared to be partly attributable to multiplicity.

'Partnerships are crucial': an evaluation of the Aboriginal Family Birthing Program in South Australia.

OBJECTIVES: To evaluate implementation and outcomes of the Aboriginal Family Birthing Program (AFBP), which provides culturally competent antenatal, intrapartum and early postnatal care for Aboriginal families across South Australia (SA). METHODS: Analysis of births to Aboriginal women in SA 2010-2012; interviews with health professionals and AFBP clients. RESULTS: Around a third of all Aboriginal women giving birth in SA 2010-2012 (n=486) attended AFBP services. AFBP women were more likely to be more socially disadvantaged, have poorer pregnancy health and to have inadequate numbers of antenatal visits than Aboriginal women attending other services. Even with greater social disadvantage and higher clinical complexity, pregnancy outcomes were similar for AFBP and other Aboriginal women. Interviews with 107 health professionals (including 20 Aboriginal Maternal and Infant Care (AMIC) workers) indicated differing levels of commitment to the model, with some lack of clarity about AMIC workers and midwives roles. Interviews with 20 AFBP clients showed they highly valued care from another Aboriginal woman. CONCLUSIONS: Despite challenges, the AFBP reaches out to women with the greatest need, providing culturally appropriate, effective care through partnerships. Implications for Public Health: Programs like the AFBP need to be expanded and supported to improve maternal and child health outcomes for Aboriginal families.

Seasonality of gestational diabetes mellitus: a South Australian population study.

OBJECTIVE: To investigate whether there is a seasonal variation in the incidence of gestational diabetes mellitus (GDM). RESEARCH DESIGN AND METHODS: This retrospective cohort study of 60 306 eligible South Australian live-born singletons during 2007-2011 recorded in the South Australian Perinatal Statistics Collection (SAPSC) examined the incidence of GDM in relation to estimated date of conception (eDoC). Fourier series analysis was used to model seasonal trends. RESULTS: During the study period, 3632 (6.0%) women were diagnosed with GDM. Seasonal modeling showed a strong relation between GDM and eDoC (p<0.001). Unadjusted and adjusted models (adjusted for maternal age, body mass index (BMI), parity, ethnicity, socioeconomic status, and chronic hypertension) demonstrated the presence of a peak incidence occurring among pregnancies with eDoC in winter (June/July/August), with a trough for eDoc in summer (December/January/February). As this was a retrospective study, we could only use variables that had been collected as part of the routine registration system, the SAPSC. CONCLUSIONS: This study is the first population-based study to demonstrate a seasonal variation for GDM. Several maternal lifestyle and psychosocial factors associated with seasonality and GDM may be influential in the pathophysiologic mechanisms of GDM. Ambient temperature, physical activity, nutrient intake, and vitamin D levels may affect maternal physiology, and fetal and placental development at the cellular level and contribute to the development of GDM. The mechanisms underlying these possible associations are not fully understood and warrant further investigation.

Sexual Dimorphism in Adverse Pregnancy Outcomes - A Retrospective Australian Population Study 1981-2011.

OBJECTIVES: Sexual inequality starts in utero. The contribution of biological sex to the developmental origins of health and disease is increasingly recognized. The aim of this study was to assess and interpret sexual dimorphisms for three major adverse pregnancy outcomes which affect the health of the neonate, child and potentially adult. METHODS: Retrospective population-based study of 574,358 South Australian singleton live births during 1981-2011. The incidence of three major adverse pregnancy outcomes [preterm birth (PTB), pregnancy induced hypertensive disorders (PIHD) and gestational diabetes mellitus (GDM)] in relation to fetal sex was compared according to traditional and fetus-at-risk (FAR) approaches. RESULTS: The traditional approach showed male predominance for PTB [20-24 weeks: Relative Risk (RR) M/F 1.351, 95%-CI 1.274-1.445], spontaneous PTB [25-29 weeks: RR M/F 1.118, 95%-CI 1.044-1.197%], GDM [RR M/F 1.042, 95%-CI 1.011-1.074], overall PIHD [RR M/F 1.053, 95%-CI 1.034-1.072] and PIHD with term birth [RR M/F 1.074, 95%-CI 1.044-1.105]. The FAR approach showed that males were at increased risk for PTB [20-24 weeks: RR M/F 1.273, 95%-CI 1.087-1.490], for spontaneous PTB [25-29 weeks: RR M/F 1.269, 95%-CI 1.143-1.410] and PIHD with term birth [RR M/F 1.074, 95%-CI 1.044-1.105%]. The traditional approach demonstrated female predominance for iatrogenic PTB [25-29 weeks: RR M/F 0.857, 95%-CI 0.780-0.941] and PIHD associated with PTB [25-29 weeks: RR M/F 0.686, 95%-CI 0.581-0.811]. The FAR approach showed that females were at increased risk for PIHD with PTB [25-29 weeks: RR M/F 0.779, 95%-CI 0.648-0.937]. CONCLUSIONS: This study confirms the presence of sexual dimorphisms and presents a coherent framework based on two analytical approaches to assess and interpret the sexual dimorphisms for major adverse pregnancy outcomes. The mechanisms by which these occur remain elusive, but sex differences in placental gene expression and function are likely to play a key role. Further research on sex differences in placental function and maternal adaptation to pregnancy is required to delineate the causal molecular mechanisms in sex-specific pregnancy outcome. Identifying these mechanisms may inform fetal sex specific tailored antenatal and neonatal care.

Age range for inclusion affects ascertainment by birth defects registers.

BACKGROUND: The South Australian Birth Defects Register (SABDR) has collected the date of diagnosis of notified birth defects since the 2005 birth year cohort. This study aims to document the age at diagnosis for each of the main diagnostic categories of birth defects, to produce a profile of when defects are diagnosed. METHODS: Deidentified data were extracted from the SABDR for birth years 2005 to 2007. Each birth defect was assigned to a mutually exclusive date of diagnosis category (termination/stillbirth; neonatal [birth-28 days]; 1 month-1 year; 1-2 years; 2-3 years; 3-4 years; 4-5 years; unspecified). Each defect was also grouped according to the International Classification of Diseases Ninth edition-British Paediatric Association major diagnostic categories (nervous, cardiovascular, respiratory, gastrointestinal, urogenital, musculoskeletal, chromosomal, metabolic, hematological/immune, other). RESULTS: There were 6419 defects identified in 3676 individuals, and 98.6% of defects had a diagnosis date recorded. Terminations of pregnancy/stillbirths accounted for 20.3% of defects notified, and a further 46.7% of defects were diagnosed within the neonatal period. A total of 81.5% of defects were diagnosed by 1 year of age. An additional 17.2% of defects were diagnosed between the ages of 1 and 5 years. There were wide differences in age at diagnosis between the major diagnostic categories. CONCLUSION: This study highlights the value of birth defect registers collecting information about birth defects from terminations of pregnancy, stillbirths, and live births up to a child's fifth birthday. Reviewing diagnosis date provides insight into the pattern of diagnosis of different birth defects. This provides valuable information to medical specialists and researchers regarding the interpretation of information from birth defect data collections. Birth Defects Research (Part A) 106:761-766, 2016. © 2016 Wiley Periodicals, Inc.

Increase in late diagnosed developmental dysplasia of the hip in South Australia: risk factors, proposed solutions.

OBJECTIVES: To review evidence for the increased incidence of late diagnosed developmental dysplasia of the hip (DDH) in South Australia; to identify perinatal risk factors associated with late DDH in babies born between 2003 and 2009 in SA. DESIGN: Linkage study of data collected prospectively by the South Australian Birth Defects Register (SABDR) and the Pregnancy Outcome Statistics Unit (SA Department of Health), supplemented by medical records review. PARTICIPANTS: All children born 2003-2009 in whom DDH was diagnosed between 3 months and 5 years of age and notified to the SABDR (data inclusion range, 2003-2014). Children with teratological hip dislocations and other major congenital abnormalities were excluded. MAIN OUTCOME MEASURES: Uni- and multivariable analyses were performed to identify perinatal risk factors for late diagnosed DDH. RESULTS: The incidence of late diagnosed DDH in babies born 2003-2009 was 0.77 per 1000 live births, contrasting with the figure of 0.22 per 1000 live births during 1988-2003. Significant perinatal risk factors were birth in a rural hospital (v metropolitan public hospital: odds ratio [OR], 2.47; CI, 1.37-4.46; P = 0.003), and being the second child (v being the first-born: OR, 1.69; CI, 1.08-2.66; P = 0.023). Breech presentation was highly significant as a protective factor when compared with cephalic presentation (OR, 0.25; CI, 0.12-0.54; P < 0.001). CONCLUSIONS: The incidence of late DDH has increased in SA despite an ongoing clinical screening program. Increased awareness, education, and avoidance of inappropriate lower limb swaddling are necessary to reverse this trend.

Anaemia of pregnancy, perinatal outcomes and children's developmental vulnerability: a whole-of-population study.

BACKGROUND: There is limited longitudinal data from high-income countries on the sequelae of anaemia during pregnancy. The aim of this study is to examine whether anaemia of pregnancy is associated with adverse perinatal outcomes and with children's developmental vulnerability. METHODS: We conducted a population-based study to link routinely collected government administrative data that involved all live births in the state of South Australia 1999-2005 (n = 124 061) and a subset for whom developmental data were collected during a national census of children attending their first year of school in 2009 (n = 13 654). Perinatal outcomes were recorded by midwives using a validated, standardised form. Development was recorded by schoolteachers using the Australian Early Development Index (AEDI). Children in the lowest 10% of AEDI scores are indicative of developmental vulnerability. RESULTS: There were 8764/124 061 (7.1%) cases of anaemia. After adjustment for a range of potentially confounding factors, anaemia of pregnancy was associated with a higher risk of fetal distress [incident rate ratio (IRR) 1.20 [95% CI 1.13, 1.27]] and preterm birth <37 weeks gestation (IRR 1.23 [1.15, 1.31]), slightly higher birthweight [14 g (2, 26)] and newborns were less likely to require resuscitation (IRR 0.94 [0.91, 0.097]). Anaemia of pregnancy was not associated with children's developmental vulnerability after adjustment for maternal, obstetric and sociodemographic covariables, either in complete case analyses (n = 11 949) or after imputation for missing data (n = 13 654). CONCLUSIONS: Anaemia of pregnancy is associated with perinatal complications but not with children's developmental vulnerability at school entry.

The impact of Aboriginal status, cigarette smoking and smoking cessation on perinatal outcomes in South Australia.

OBJECTIVE: To assess the impact of Aboriginal status, active cigarette smoking and smoking cessation during pregnancy on perinatal outcomes. DESIGN: Retrospective cohort study from 1 January 1999 to 31 December 2008. SETTING: All singleton births in South Australia. PARTICIPANTS: Population-based birth records of pregnancies to Aboriginal women (n = 4245) and non-Aboriginal women (n = 167 746). MAIN OUTCOME MEASURES: Adjusted odds ratios (aORs) and 95% CIs for adverse maternal and neonatal outcomes according to Aboriginal status and maternal smoking in pregnancy. RESULTS: Active cigarette smoking during pregnancy was associated with an increased risk of adverse perinatal outcomes, including premature labour (Aboriginal, 1-10 cigarettes per day: aOR, 1.69; 95% CI, 1.28-2.23; non-Aboriginal, 1-10 cigarettes per day: aOR, 1.46; 95% CI, 1.34-1.58), preterm birth (Aboriginal, 1-10 cigarettes per day: aOR, 1.40; 95% CI, 1.14-1.73; non-Aboriginal, 1-10 cigarettes per day: aOR, 1.48; 95% CI, 1.39-1.57), intrauterine growth restriction (Aboriginal, 1-10 cigarettes per day: aOR, 2.33; 95% CI, 1.77-3.08; non-Aboriginal, 1-10 cigarettes per day: aOR, 2.65; 95% CI, 2.48-2.83) and small for gestational age (Aboriginal, 1-10 cigarettes per day: aOR, 2.49; 95% CI, 2.06-3.00; non-Aboriginal, 1-10 cigarettes per day: aOR, 2.29; 95% CI, 2.20-2.40). For both Aboriginal and non-Aboriginal women who smoked 11 or more cigarettes per day the aOR for these outcomes increased. Smoking cessation in the first trimester reduced these risks to levels comparable with non-smokers. The risk of each adverse outcome was greater in Aboriginal than non-Aboriginal women for all smoking categories; however, interactions between Aboriginal status and smoking were not significant, indicating an equal contribution of smoking to poor outcomes in both populations. CONCLUSIONS: Smoking cessation or reduction during pregnancy would significantly improve outcomes in both Aboriginal and non-Aboriginal women. This should be made a clear priority to improve pregnancy outcomes for all women.

The association between increasing maternal age at first birth and decreased rates of spontaneous vaginal birth in South Australia from 1991 to 2009.

BACKGROUND: Caesarean section rates in Australia rose over the period 1999-2009, as did maternal age at first birth. The contribution of the rise of maternal age to the rise in caesarean sections remains unclear. AIMS: To estimate the effect of increasing maternal age on the incidence of emergency caesarean section or instrumental delivery in term singleton first births in South Australia. METHODS: We undertook a population-based study of 117 981 term singleton first births, which followed labour during the period 1991-2009, using data from the South Australian Perinatal Statistics Collection. The main outcome measures were deliveries other than spontaneous vaginal births (SVB) (emergency caesarean section or instrumental birth) and emergency caesarean section alone. Logistic regression analysis was performed. RESULTS: Increasing maternal age at first birth was found to be associated with delivery other than SVB and emergency caesarean section. The adjusted odds of delivery other than SVB increased multiplicatively by approximately 1.49 (95% CI, 1.47-1.51) per five-year rise in maternal age, and the odds of emergency caesarean section increased multiplicatively by approximately 1.39 (95% CI, 1.37-1.42) per five-year rise. Although there are likely to be many reasons for the effect, increases in maternal age at first birth made a contribution in up to 75% of the observed increase in delivery other than SVB from 44.0% to 49.6% over the study period. CONCLUSIONS: Rising maternal age at first birth appeared to contribute to a large proportion of the increase in deliveries other than SVB in South Australia.

Perinatal outcomes following maternal asthma and cigarette smoking during pregnancy.

Does cigarette smoking in pregnancy explain the increased risk of adverse perinatal outcomes that occur with maternal asthma or does it compound the effect? Using population based birth records, a retrospective analysis was conducted of all singleton pregnancies in South Australia over 10 years (1999-2008; n=172 305), examining maternal asthma, cigarette smoking and quantity of smoking to estimate odds ratios. Compared with nonasthmatic females who did not smoke during pregnancy, both asthmatic females who smoked and those who did not smoke during pregnancy had a significantly increased risk of gestational diabetes, antepartum haemorrhage, polyhydramnios, premature rupture of membranes, emergency Caesarean section, and the child being small for gestational age and having congenital abnormalities. These associations suggest that asthma, independently of maternal smoking, increases the risk of these adverse perinatal outcomes. Maternal smoking was itself associated with an increased risk of a number of poor neonatal outcomes, with a dose-response relationship observed. Notably, maternal asthma combined with cigarette smoking significantly increased the risk of preterm birth and urinary tract infections to a greater degree than with either exposure alone. Maternal asthma and cigarette smoking during pregnancy are both independently associated with adverse perinatal outcomes and, combined, compound the risk of preterm birth and urinary tract infections.

An increase in neural tube defect notifications, South Australia, 2009-2010.

INTRODUCTION: In South Australia, reporting of live births, stillbirths of at least 20 weeks or 400 g birth weight, termination of pregnancies and congenital anomalies is mandated. We describe the investigation of an increase in notifications of neural tube defects (NTDs) in South Australia in 2009 and 2010 using data from several surveillance systems. METHODS: NTD trend data from 1966 to 2010 were reviewed. Comparisons of pregnancies affected by an NTD in 2009 and 2010 were made with pregnancies affected by an NTD in the period 2003-2008 and with all pregnancies in 2009 and 2010. Statistical analysis was undertaken using Poisson regression, χ(2) or Fisher's exact tests. RESULTS: The prevalence of NTD-affected pregnancies was 1.95 per 1000 births (39 cases) in 2010 and 1.91 per 1000 births in 2009 (38 cases), the highest annual rates since 1991. Case series comparisons indicated women with NTD-affected pregnancies in 2009 and 2010 were less likely to be Caucasian compared with women who had NTD-affected pregnancies in the period 2003-2008. Women born in the Middle East and African region (n = 7) were significantly more likely to have NTD-affected pregnancies in the years 2009 and 2010 (relative risk: 3.03; 95% confidence interval: 1.39-6.62) compared with women born in the Oceania region. DISCUSSION: The increased notifications of NTDs can only be partially explained by the increase in numbers of women from the Middle East and African region, with no other contributory causes revealed. This analysis highlighted areas where prevention efforts should be strengthened and surveillance data improved.

Pregnancy outcomes for nulliparous women of advanced maternal age in South Australia, 1998-2008.

BACKGROUND: Child bearing in the later reproductive years has become increasingly common in Australia with potential implications for clinical practice. AIM: To examine pregnancy outcomes for nulliparous women of advanced maternal age with singleton pregnancies. METHODS: A retrospective population-based cohort study was conducted to compare the pregnancy outcomes for women aged 35-39 years and ≥40 years with women aged 25-29 years, analysing 34 695 records from the South Australian Perinatal Database between 1998 and 2008. RESULTS: Pre-existing hypertension [relative risks (RR) 1.98 and 2.94 for women aged 35-39 years and ≥40 years, respectively], placenta praevia (RR 2.88 and 3.68), suspected intrauterine growth restriction (RR 1.33 and 1.77) and gestational diabetes (RR 1.97 and 2.53) increased with age. Women of advanced maternal age were more likely to have not laboured prior to birth (RR 2.19 and 3.28), be induced (RR 1.12 and 1.27) and have a breech presentation (RR 1.57 and 1.60). The likelihood of fetal distress increased with advancing maternal age (RR 1.15 and 1.24). Regression analyses revealed women of advanced maternal age were significantly more likely to have small for gestational age infants [adjusted odds ratios (AOR) 1.26 and 1.50], preterm birth (AOR 1.26 and 1.43), elective caesarean [relative risk ratios (RRR) 2.55 and 4.52], emergency caesarean (RRR 1.59 and 2.21) and experience a perinatal death (RRR 1.94 and 2.18). CONCLUSIONS: The likelihood of pre-existing medical conditions, obstetric complications, adverse labour and birth outcomes and complications increased with advancing maternal age. Advanced maternal age was also independently associated with selected adverse pregnancy and infant outcomes.

Can shoulder dystocia be reliably predicted?

AIMS: To evaluate factors reported to increase the risk of shoulder dystocia, and to evaluate their predictive value at a population level. METHODS: The South Australian Pregnancy Outcome Unit's population database from 2005 to 2010 was accessed to determine the occurrence of shoulder dystocia in addition to reported risk factors, including age, parity, self-reported ethnicity, presence of diabetes and infant birth weight. Odds ratios (and 95% confidence interval) of shoulder dystocia was calculated for each risk factor, which were then incorporated into a logistic regression model. Test characteristics for each variable in predicting shoulder dystocia were calculated. RESULTS: As a proportion of all births, the reported rate of shoulder dystocia increased significantly from 0.95% in 2005 to 1.38% in 2010 (P = 0.0002). Using a logistic regression model, induction of labour and infant birth weight greater than both 4000 and 4500 g were identified as significant independent predictors of shoulder dystocia. The value of risk factors alone and when incorporated into the logistic regression model was poorly predictive of the occurrence of shoulder dystocia. CONCLUSIONS: While there are a number of factors associated with an increased risk of shoulder dystocia, none are of sufficient sensitivity or positive predictive value to allow their use clinically to reliably and accurately identify the occurrence of shoulder dystocia.