Tanya A. Nippita

Premature ovarian failure: a review.

Objectives To present an updated review on the etiology, consequences and management of premature ovarian failure. Design A search of the English language literature using the Cochrane Library database and Medline 1966–2006, with a hand search of the references. Conclusion Premature ovarian failure is defined as the occurrence of amenorrhea, hypergonadotropinemia and estrogen deficiency in women under the age of 40 years, with the prevalence being 0.9–1.2%. In the majority of cases, the etiology is unknown, but known causes include chemotherapy, radiotherapy, surgery, genetic disorders, particularly involving the X chromosome, associations with autoimmune diseases, infections, smoking and other toxins. The three critical issues of management in these women are the effect of the diagnosis on the psychological health of the patient, the consequent infertility and the long- and short-term effects of estrogen deficiency arising from ovarian decline. Promising methods of screening for premature ovarian failure are being developed.

Variation in hospital caesarean section rates and obstetric outcomes among nulliparae at term: a population-based cohort study.

To explore the variation in hospital caesarean section (CS) rates for nulliparous women, to determine whether different case‐mix, labour and delivery, and hospital factors can explain this variation and to examine the association between hospital CS rates and outcomes.

Association of prelabor cesarean delivery with reduced mortality in twins born near term

OBJECTIVE: To examine short-term and longer-term outcomes for twins born at or near term, comparing prelabor cesarean delivery with birth after a trial of labor. METHODS: This study was conducted on a retrospective cohort of twin pregnancies delivered at 36 weeks of gestation or greater from 2000 to 2009. Pregnancies with an antenatal death, lethal anomaly, birth weight discordance 25% or more, or birth weight less than 2,000 g or more than 4,000 g were excluded. Outcomes included severe hypoxia, stillbirth and neonatal death, and hospital admissions or death during the first 5 years of life. RESULTS: Approximately 45% of 7,099 twin pregnancies were delivered by prelabor cesarean delivery. Compared with delivery after labor, prelabor cesarean delivery was associated with significantly reduced risks of adverse neonatal and child outcomes including severe birth hypoxia (0.08% compared with 0.75%, relative risk 0.10, 95% confidence interval [CI] 0.04–0.26), neonatal death (0.00% compared with 0.15%, relative risk 0.05, 95% CI 0.00–0.82), and death up to 5 years of age (0.16% compared with 0.40%, relative risk 0.41, 95% CI 0.20–0.85). Whereas total mortality for first twins was similar after labor (0.15%) compared with prelabor cesarean delivery (0.16%), total mortality was four times more common in second twins born after labor (0.64%) compared with second twins born after prelabor cesarean delivery (0.16%). CONCLUSION: Compared with prelabor cesarean delivery, twin pregnancies at and beyond 36 weeks of gestation delivered after labor have increased risks for birth outcomes associated with hypoxia, with second twins having significantly increased mortality up to 5 years of age. However, the absolute mortality rate for relatively uncomplicated twin pregnancies delivered at or near term is low and needs to be balanced against maternal morbidity. LEVEL OF EVIDENCE: II

Incidence and outcomes of pregnancy‐associated melanoma in New South Wales 1994–2008

There is controversy about the interaction between melanoma and pregnancy. There is a lack of Australian data on pregnancy outcomes associated with melanoma in pregnancy, despite Australia having the highest incidence of melanoma in the world.

Heart valve prostheses in pregnancy: outcomes for women and their infants.

Background As the prognosis of women with prosthetic heart valves improves, and increasing number are contemplating and undertaking pregnancy. Accurate knowledge of perinatal outcomes is essential, assisting counseling and guiding care. The aims of this study were to assess outcomes in a contemporary population of women with heart valve prostheses undertaking pregnancy and to compare outcomes for women with mechanical and bioprosthetic prostheses. Methods and Results Longitudinally linked population health data sets containing birth and hospital admissions data were obtained for all women giving birth in New South Wales, Australia, 2000–2011. This included information identifying presence of maternal prosthetic heart valve. Cardiovascular and birth outcomes were evaluated. Among 1 144 156 pregnancies, 136 involved women with a heart valve prosthesis (1 per 10 000). No maternal mortality was seen among these women, although the relative risk for an adverse event was higher than the general population, including severe maternal morbidity (139 versus 14 per 1000 births, rate ratio [RR]=9.96, 95% CI 6.32 to 15.7), major maternal cardiovascular event (44 versus 1 per 1000, RR 34.6, 95% CI 14.6 to 81.6), preterm birth (183 versus 66 per 1000, RR=2.77, 95% CI 1.88 to 4.07), and small‐for‐gestational‐age infants (193 versus 95 per 1000, RR=2.03, 95% CI 1.40 to 2.96). There was a trend toward increased maternal and perinatal morbidity in women with a mechanical valve compared with those with a bioprosthetic valve. Conclusions Pregnancies in women with a prosthetic heart valve demonstrate an increased risk of an adverse outcome, for both mothers and infants, compared with pregnancies in the absence of heart valve prostheses. In this contemporary population, the risk was lower than previously reported.

Variation in hospital rates of induction of labour: a population-based record linkage study

Objectives To examine interhospital variation in rates of induction of labour (IOL) to identify potential targets to reduce high rates of practice variation. Design Population-based record linkage cohort study. Setting New South Wales, Australia, 2010–2011. Participants All women with live births of ≥24 weeks gestation in 72 hospitals. Primary outcome measure Variation in hospital IOL rates adjusted for differences in case-mix, according to 10 mutually exclusive groups derived from the Robson caesarean section classification; groups were categorised by parity, plurality, fetal presentation, prior caesarean section and gestational age. Results The overall IOL rate was 26.7% (46 922 of 175 444 maternities were induced), ranging from 9.7% to 41.2% (IQR 21.8–29.8%) between hospitals. Nulliparous and multiparous women at 39–40 weeks gestation with a singleton cephalic birth were the greatest contributors to the overall IOL rate (23.5% and 20.2% of all IOL respectively), and had persisting high unexplained variation after adjustment for case-mix (adjusted hospital IOL rates ranging from 11.8% to 44.9% and 7.1% to 40.5%, respectively). In contrast, there was little variation in interhospital IOL rates among multiparous women with a singleton cephalic birth at ≥41 weeks gestation, women with singleton non-cephalic pregnancies and women with multifetal pregnancies. Conclusions 7 of the 10 groups showed high or moderate unexplained variation in interhospital IOL rates, most pronounced for women at 39–40 weeks gestation with a singleton cephalic birth. Outcomes associated with divergent practice require determination, which may guide strategies to reduce practice variation.

Maternal and neonatal outcomes following abnormally invasive placenta: a population‐based record linkage study

Abnormally invasive placenta involves abnormal adherence of the placenta to the myometrium and is associated with severe pregnancy complications such as blood transfusion and hysterectomy. Knowledge of outcomes has been limited by small sample sizes and a focus on maternal rather than neonatal outcomes. This study uses population‐level data collected over 10 years to investigate maternal and neonatal outcomes and trends in incidence of abnormally invasive placenta (also known as placenta accreta, increta and percreta).

Venous thromboembolism prophylaxis during and following caesarean section: a survey of clinical practice

Caesarean section (CS) is a significant risk factor for venous thromboembolism; however, the optimal method of thromboprophylaxis around the time of CS is unknown.

Red blood cell transfusion after postpartum haemorrhage and breastmilk feeding at discharge: A population‐based study

Recently released patient blood management guidelines for maternity patients in Australia highlighted the lack of evidence on functional outcomes post‐transfusion.

Inter-hospital variations in labor induction and outcomes for nullipara: an Australian population-based linkage study.

This study aimed to describe variation in inter‐hospital induction of labor (IOL) rates, determine whether variation is explained by individual and hospital factors and examine birth outcomes.