A hospital-based cohort study of gender and gestational age-specific body fat percentage at birth.

BACKGROUND: Birthweight is the most commonly used proxy marker but does not adequately define true nutritional status. Modalities like DXA (dual energy x-ray absorptiometry) and TOtal Body Electric Conductivity (TOBEC) have been validated to assess body composition but their accuracy in neonates has not been established. The PEAPOD (COSMED, Rome Italy) has been validated as an accurate tool for measuring percentage body fat (%BF) in newborns. The study aim was to determine the gender-specific %BF percentiles at different gestations (35-41 weeks) for a healthy population of newborn infants. A secondary aim was to determine whether there is any relationship between %BF and neonatal condition at birth (cord gas measurement). METHODS: %BF was measured using air displacement plethysmography (PEAPOD) within 6 h of birth. RESULTS: There is an increase in the mean %BF with increasing gestation for female and males from 36 weeks' gestation in the 7667 infants who underwent assessment. Females have a higher %BF than their male equivalents. There was no correlation between %BF and cord pH. CONCLUSION: Gender and gestation are both important in determining the quantiles and mean %BF at birth. There was no correlation between low cord pH and %BF. IMPACT: Measuring the percentage body fat (PEAPOD) at birth is a useful marker of an infant's nutritional status. This is the largest hospital-based cohort of gestational age and gender-specific %BF in healthy newborns. The normative graphs from this study will help to accurately determine high-risk infants with low %BF so they can be monitored appropriately.

Cesarean delivery: Trend in indications over three decades within a major city hospital network.

INTRODUCTION: The cesarean delivery rate has been increasing globally in recent decades. The reasons for this are complex and subject to ongoing debate. Investigation of the indications for cesarean delivery and how these have changed over an extended period of time could provide insight into the reasons for changing obstetric practice. Our objective was to explore contributing factors to the increasing rate of cesarean delivery by examining the incidence of and indications for cesarean delivery over the past three decades at our institutions. MATERIAL AND METHODS: We conducted a retrospective observational study of all cesarean deliveries, from 24 weeks' gestational age onwards, within an inner-city hospital network in Sydney, Australia, between August 1989 and December 2016. The primary outcome measures were the rates of and indications for emergency and planned cesarean delivery. We also examined our data within the Robson 10-Group Classification system. RESULTS: There were 147 722 births over the study period, with 37 309 cesarean deliveries for an overall rate of 25.3%. The rate of cesarean delivery increased from 18.7% in 1989-1994 (8.7% emergency, 10% planned) to 30.4% in 2010-2016 (11.4% emergency, 19% planned). Emergency cesarean delivery for slow progress increased from 3.4% to 5.5% of all births (a relative increase of 62%) and other emergency cesareans mainly performed for suspected intrapartum fetal compromise increased from 5.2% to 5.6% (a relative increase of 8%). Previous uterine surgery (predominantly cesarean section) was the largest contributor to the increase in planned procedures from 3.8% to 9.0% of all births, and 29% of all cesarean deliveries. Primary cesarean delivery for planned antenatal fetal indications, previous pregnancy problems, multiple gestation and maternal choice all increased substantially in combined rate from 0.7% to 4.9%. Cesarean rates in Robson groups 6, 7 and 8 (term breech and multiple gestations) increased most over time. CONCLUSIONS: The increased rate of cesarean delivery is mainly attributable to a greater number of procedures performed for slow progress in labor, breech presentation or repeat cesarean section.

Outcomes of induction of labour in nulliparous women at 38 to 39 weeks pregnancy by clinical indication: An observational study.

BACKGROUND: Knowledge of the outcomes of induction of labour for different indications is sparse. AIMS: To describe the mode of birth and other outcomes for nulliparous women induced at 38-39 weeks gestational age by indication for induction of labour. MATERIAL AND METHODS: This was a retrospective observational study in a tertiary referral hospital, and a metropolitan teaching hospital in Sydney. The study population was nulliparous women with induction of labour at 38 or 39 completed weeks of pregnancy and a singleton, cephalic presenting baby planning a vaginal birth, from 2009 to 2016. The indication for induction of labour was classified into 12 groups. Mode of birth and other maternal and perinatal outcomes were described in each group, for women who spontaneously laboured at 38 or 39 weeks, and for women who gave birth from 40 completed weeks onward. The main outcome measure was mode of birth. RESULTS: There were 3330 women with induction of labour at 38 or 39 weeks gestation. Rates of vaginal birth varied widely, ranging from 54% when the indication for induction was suspected large fetus, to 82% when the indication was suspected fetal compromise, and was 74% overall. Indications for caesarean delivery also varied by indication for induction. Among women giving birth ≥40 weeks gestational age, 75% had a vaginal birth. CONCLUSIONS: In nulliparous women, rates of vaginal birth following induction of labour at 38 or 39 weeks gestation vary widely according to the indication for induction. These data are useful for antenatal counselling.

The association between induction of labour at 38 to 39 weeks pregnancy and indication for caesarean delivery: An observational study.

BACKGROUND: Induction of labour is associated with a reduction in caesarean delivery, but the mechanism of action and which groups of women might benefit remain unknown. AIMS: To assess the association between induction of labour at 38-39 weeks pregnancy, and caesarean delivery: (i) overall; (ii) for slow progress in labour; and (iii) for suspected fetal compromise. MATERIAL AND METHODS: Retrospective observational study in two Sydney hospitals from 2009 to 2016, among nulliparous women with induction of labour at 38 or 39 completed weeks pregnancy and a singleton, cephalic presenting fetus. The comparator was all planned vaginal births beyond 39(+1/7) weeks, whether or not labour was induced. Binary and multinomial multiple logistic regressions adjusting for multiple confounders were performed. RESULTS: There were 2388 and 15 259 women in the study and comparison groups respectively. Induction of labour was associated with caesarean delivery overall only for women <25 years of age (adjusted odds ratio 1.63; 95% CI 1.17-2.27) and was not associated with caesarean delivery for slow progress. Induction of labour was positively associated with increased caesarean delivery for suspected fetal compromise among young women (<30 years), with the association weakening as maternal age increased. The association between induction of labour and caesarean delivery was different for slow progress compared with suspected compromise (P = 0.005). CONCLUSIONS: Induction of labour has different effects on the likelihood of caesarean delivery for slow progress and for suspected fetal compromise. Women <30 years of age are at higher risk of caesarean delivery for suspected fetal compromise, potentially due to uterine hyperstimulation.