Jillian A. Patterson

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.

Unexplained variation in hospital caesarean section rates.

Objectives: To assess recent hospital caesarean section (CS) rates in New South Wales, adjusted for casemix; to quantify the amount of variation that can be explained by casemix differences; and to examine the potential impact on the overall CS rate of reducing variation in practice.

Immediate delivery compared with expectant management after preterm pre-labour rupture of the membranes close to term (PPROMT trial): a randomised controlled trial.

BACKGROUND Preterm pre-labour ruptured membranes close to term is associated with increased risk of neonatal infection, but immediate delivery is associated with risks of prematurity. The balance of risks is unclear. We aimed to establish whether immediate birth in singleton pregnancies with ruptured membranes close to term reduces neonatal infection without increasing other morbidity. METHODS The PPROMT trial was a multicentre randomised controlled trial done at 65 centres across 11 countries. Women aged over 16 years with singleton pregnancies and ruptured membranes before the onset of labour between 34 weeks and 36 weeks and 6 days weeks who had no signs of infection were included. Women were randomly assigned (1:1) by a computer-generated randomisation schedule with variable block sizes, stratified by centre, to immediate delivery or expectant management. The primary outcome was the incidence of neonatal sepsis. Secondary infant outcomes included a composite neonatal morbidity and mortality indicator (ie, sepsis, mechanical ventilation ≥24 h, stillbirth, or neonatal death); respiratory distress syndrome; any mechanical ventilation; and duration of stay in a neonatal intensive or special care unit. Secondary maternal outcomes included antepartum or intrapartum haemorrhage, intrapartum fever, postpartum treatment with antibiotics, and mode of delivery. Women and caregivers could not be masked, but those adjudicating on the primary outcome were masked to group allocation. Analyses were by intention to treat. This trial is registered with the International Clinical Trials Registry, number ISRCTN44485060. FINDINGS Between May 28, 2004, and June 30, 2013, 1839 women were recruited and randomly assigned: 924 to the immediate birth group and 915 to the expectant management group. One woman in the immediate birth group and three in the expectant group were excluded from the primary analyses. Neonatal sepsis occurred in 23 (2%) of 923 neonates whose mothers were assigned to immediate birth and 29 (3%) of 912 neonates of mothers assigned to expectant management (relative risk [RR] 0·8, 95% CI 0·5-1·3; p=0·37). The composite secondary outcome of neonatal morbidity and mortality occurred in 73 (8%) of 923 neonates of mothers assigned to immediate delivery and 61 (7%) of 911 neonates of mothers assigned to expectant management (RR 1·2, 95% CI 0·9-1·6; p=0·32). However, neonates born to mothers in the immediate delivery group had increased rates of respiratory distress (76 [8%] of 919 vs 47 [5%] of 910, RR 1·6, 95% CI 1·1-2·30; p=0·008) and any mechanical ventilation (114 [12%] of 923 vs 83 [9%] of 912, RR 1·4, 95% CI 1·0-1·8; p=0·02) and spent more time in intensive care (median 4·0 days [IQR 0·0-10·0] vs 2·0 days [0·0-7·0]; p<0·0001) compared with neonates born to mothers in the expectant management group. Compared with women assigned to the immediate delivery group, those assigned to the expectant management group had higher risks of antepartum or intrapartum haemorrhage (RR 0·6, 95% CI 0·4-0·9), intrapartum fever (0·4, 0·2-0·9), and use of postpartum antibiotics (0·8, 0·7-1·0), and longer hospital stay (p<0·0001), but a lower risk of caesarean delivery (RR 1·4, 95% CI 1·2-1·7). INTERPRETATION In the absence of overt signs of infection or fetal compromise, a policy of expectant management with appropriate surveillance of maternal and fetal wellbeing should be followed in pregnant women who present with ruptured membranes close to term. FUNDING Australian National Health and Medical Research Council, the Womens and Childrens Hospital Foundation, and The University of Sydney.

Trends and outcomes of induction of labour among nullipara at term

Aim:  To determine induction trends and delivery, maternal and neonatal health outcomes by gestational age following induction at term for women having a first baby.

Trends and morbidity associated with oxytocin use in labour in nulliparas at term

To determine the trends in oxytocin use at a population level within New South Wales and to assess the maternal and neonatal morbidities associated with the use of oxytocin.

Incidence of metastatic breast cancer in an Australian population-based cohort of women with non-metastatic breast cancer at diagnosis.

Objectives: To estimate the incidence of metastatic breast cancer (MBC) in Australian women with an initial diagnosis of non‐metastatic breast cancer.

Age of blood and adverse outcomes in a maternity population.

In recent times there has been debate around whether longer storage time of blood is associated with increased rates of adverse outcomes after transfusion. It is unclear whether results focused on cardiac or critically ill patients apply to a maternity population. This study investigates whether older blood is associated with increased morbidity and readmission in women undergoing obstetric transfusion.

Obstetric anal sphincter injury rates among primiparous women with different modes of vaginal delivery

To determine whether rates of obstetric anal sphincter injuries (OASIS) are continuing to increase and whether risk of OASIS according to mode of delivery is constant over time.

WHAT FACTORS CONTRIBUTE TO HOSPITAL VARIATION IN OBSTETRIC TRANSFUSION RATES

To explore variation in red blood cell transfusion rates between hospitals, and the extent to which this can be explained. A secondary objective was to assess whether hospital transfusion rates are associated with maternal morbidity.

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.