Risk factors for late preterm and term stillbirth: A secondary analysis of an individual participant data meta-analysis.

Objective: Identify independent and novel risk factors for late-preterm (28-36 weeks) and term (≥37 weeks) stillbirth and explore development of a risk-prediction model.

Design: Secondary analysis of an Individual Participant Data (IPD) meta-analysis investigating modifiable stillbirth risk factors.

Setting: An IPD database from five case-control studies in New Zealand, Australia, the UK and an international online study.

Neonatal morbidity and small and large size for gestation: a comparison of birthweight centiles.

Objective: To compare rates of small- and large-for-gestational age (SGA and LGA) neonates using four different weight centiles, and to relate these classifications to neonatal morbidity.

Study Design: Neonates born at 33-40 weeks' gestation in a multiethnic population were classified as SGA or LGA by population reference (Fenton), population standard (INTERGROWTH), fetal growth curves (WHO), and customized (GROW) centiles. Likelihood of composite morbidity was determined compared with a common appropriate-for-gestational age referent group.

Association of Supine Going-to-Sleep Position in Late Pregnancy With Reduced Birth Weight: A Secondary Analysis of an Individual Participant Data Meta-analysis.

Importance: Supine maternal position in the third trimester is associated with reduced uterine blood flow and increased risk of late stillbirth. As reduced uterine blood flow is also associated with fetal growth restriction, this study explored the association between the position in which pregnant women went to sleep and infant birth weight.

Objective: To examine the association between supine position when going to sleep in women after 28 weeks of pregnancy and lower birth weight and birth weight centiles.

An Individual Participant Data Meta-analysis of Maternal Going-to-Sleep Position, Interactions with Fetal Vulnerability, and the Risk of Late Stillbirth.

Background: Maternal supine going-to-sleep position has been associated with increased risk of late stillbirth (≥ 28 weeks), but it is unknown if the risk differs between right and left side, and if some pregnancies are more vulnerable.

Methods: Systematic searches were undertaken for an individual-level participant data (IPD) meta-analysis of case-control studies, prospective cohort studies and randomised trials undertaken up until 26 Jan, 2018, that reported data on maternal going-to-sleep position and stillbirth. Participant inclusion criteria included gestation ≥ 28 weeks', non-anomalous, singleton pregnancies.

Evidence-based national guidelines for the management of suspected fetal growth restriction: comparison, consensus, and controversy.

Small for gestational age is usually defined as an infant with a birthweight <10th centile for a population or customized standard. Fetal growth restriction refers to a fetus that has failed to reach its biological growth potential because of placental dysfunction. Small-for-gestational-age babies make up 28-45% of nonanomalous stillbirths, and have a higher chance of neurodevelopmental delay, childhood and adult obesity, and metabolic disease.

INTERGROWTH-21st vs customized birthweight standards for identification of perinatal mortality and morbidity.

Background: The recently published INTERGROWTH-21st Project international population standard for newborn size is intended for global use, but its ability to identify small infants at risk of adverse outcomes in a general obstetric population has not been reported.

Objective: The objective of the study was to compare adverse neonatal outcomes among small-for-gestational-age (SGA) infants between the INTERGROWTH-21st standard and a customized birthweight standard (accounting for maternal characteristics of height, weight, parity, and ethnicity). We hypothesized that in a multiethnic general obstetric population in Auckland, New Zealand, a customized birthweight standard would better identify SGA infants at-risk of neonatal morbidity/mortality and stillbirth than the INTERGROWTH-21st standard.

Ethnic disparities in repeat caesarean rates at Auckland Hospital.

Background: New Zealand guidelines recommend that information regarding childbirth choices be given to women with previous caesarean, so they can make informed decisions about their care. We hypothesised that rates of trial of labour (TOL) and vaginal birth after caesarean (VBAC) would vary by women's ethnicity.

Aim: To estimate the association of ethnicity with TOL and VBAC rates.

Ethnicity and risk of caesarean section in a term, nulliparous New Zealand obstetric cohort.

Background: One in four New Zealand (NZ) women undergo caesarean section (CS); however, little is understood about how ethnicity influences CS rates. Previous NZ studies do not include many of NZ's ethnic groups and have been unable to account comprehensively for clinical risk factors.

Aim: To investigate ethnicity as an independent risk factor for elective and emergency CS in nulliparous women at term.

Gestational weight gain and adverse pregnancy outcomes in a nulliparous cohort.

Objective: Excessive gestational weight gain (GWG) is an important contributing factor to the obesity epidemic in women and is associated with pregnancy complications. We investigated the relationship between GWG and caesarean delivery in labour, large for gestational age (LGA), small for gestational age (SGA) infants and pregnancy-induced hypertension by maternal pre-pregnancy body mass index (BMI) in a contemporary nulliparous cohort.

Study Design: Using 2009 Institute of Medicine guidelines, participants in the SCOPE study (from Cork, Ireland, Auckland, New Zealand and Adelaide, Australia) were classified into GWG categories (low, normal and high) according to pre-pregnancy BMI.

Independent risk factors for infants who are small for gestational age by customised birthweight centiles in a multi-ethnic New Zealand population.

Background: Infants born small for gestational age (SGA) by customised birthweight centiles are at increased risk of adverse outcomes compared with those SGA by population centiles. Risk factors for customised SGA have not previously been described in a general obstetric population.

Aim: To determine independent risk factors for customised SGA in a multi-ethnic New Zealand population.

Maternal obesity and postpartum haemorrhage after vaginal and caesarean delivery among nulliparous women at term: a retrospective cohort study.

Background: Increasing rates of postpartum haemorrhage in developed countries over the past two decades are not explained by corresponding changes in risk factors and conjecture has been raised that maternal obesity may be responsible. Few studies investigating risk factors for PPH have included BMI or investigated PPH risk among nulliparous women. The aim of this study was to determine in a cohort of nulliparous women delivering at term whether overweight and obesity are independent risk factors for major postpartum haemorrhage (PPH ≥1000ml) after vaginal and caesarean section delivery.

Ethnicity, body mass index and risk of pre-eclampsia in a multiethnic New Zealand population.

Background: Pre-eclampsia rates are reported to vary by ethnicity; however, few studies include body mass index (BMI). Increasing BMI has a dose-dependent relationship with pre-eclampsia, and rates of overweight and obesity as well as ratios of body fat to muscle mass differ between ethnicities. We hypothesised that after adjusting for confounders, including ethnic-specific BMI, ethnicity would not be an independent risk factor for pre-eclampsia.

Risk of first-stage and second-stage cesarean delivery by maternal body mass index among nulliparous women in labor at term.

Objective: To estimate in a cohort of nulliparous women in labor at term whether cesarean delivery rates are increased in first and second stages of labor in overweight and obese women and whether being overweight or obese is an independent risk factor for cesarean delivery.

Methods: Nulliparous women recruited to the prospective Screening for Pregnancy Endpoints study who went into labor after 37 weeks of gestation were categorized according to ethnicity-specific body mass index (BMI) criteria as normal, overweight, or obese. Normal BMI was the referent.