Application of A global reference for fetal‐weight and birthweight percentiles in predicting infant mortality

Abstract

Objective To determine whether the recently published A global reference for fetal-weight and birthweight percentiles (Global Reference) improves small-(SGA), appropriate-(AGA), and large-for-gestational-age (LGA) definitions in predicting infant mortality.Design Population-based cohort study. Population Singleton births with birthweight >500 g born at 24-41 weeks of gestation.Methods We compared infant mortality rates of SGA, AGA, and LGA infants classified by three different references: the Global Reference; a commonly used birthweight reference; and Hadlock's ultrasound reference.Main outcome measures Infant mortality rates.Results Among 33 997 719 eligible liveborn singleton births, 25% of preterm and 9% of term infants were classified differently for SGA, AGA, and LGA by the Global Reference and the birthweight reference. The Global Reference indicated higher mortality rates in preterm SGA and preterm LGA infants than the birthweight reference. The mortality rate was considerably higher in infants classified as preterm SGA by the Global Reference but not by the birthweight reference, compared with the corresponding infants classified by the birthweight reference but not by the Global Reference (105.7 versus 12.9 per 1000, RR 8.17, 95% CI 7.38-9.06). Yet, the differences in mortality rates were much smaller in term infants than in preterm infants. Black infants had a particularly higher mortality rate than other races in AGA and LGA preterm and term infants.Conclusions In respect to the commonly used birthweight reference, the Global Reference increases the identification of infant deaths by improved classification of abnormal newborn size at birth, and these advantages were more obvious in preterm than in term infants.

Effects of antenatal exercise in overweight and obese pregnant women on maternal and perinatal outcomes: a randomised controlled trial

“…Placental weight was measured untrimmed by delivery staff. Perinatal outcomes were defined as follows: large‐for‐gestational‐age (LGA)—birthweight >90th percentile; small‐for‐gestational‐age (SGA)—birthweight <10th percentile for gestational age; perinatal asphyxia—5‐minute Apgar score <7; hypoglycaemia—blood glucose <2.5 mmol/l, requiring therapy other than supplemental feeding; respiratory distress—any non‐specific respiratory distress needing respiratory support/oxygen therapy. Length of postnatal hospital stay was defined as the time between delivery and home discharge.…”

Adverse Maternal and Birth Outcomes in Women Admitted to Hospital for Hyperemesis Gravidarum: a Population‐Based Cohort Study

“…We assessed the following adverse birth outcomes amongst live matched singletons: need for neonatal care (special, intensive, and very intensive); resuscitation method (drugs, drugs and mask, tube, tube and drugs); birthweight (<2500, 2500–3999, and ≥4000 g). small for gestational age (SGA) or large for gestational age (LGA), defined as less than the 10th centile and more than the 90th centile, respectively, were estimated using the Global Reference standard that accounts for mean differences in birthweight by maternal race …”

Associations of maternal pre-pregnancy body mass index and gestational weight gain with birth outcomes in Shanghai, China

“…Clinical estimates of gestational age (ultrasound) were also obtained from maternal medical records. Gestational age was estimated based on the date of the self-reported LMP; if the LMP was unreliable or if there was a significant discordance between the clinical estimate and LMP (>2 weeks), the clinical estimation of gestational age was used22. Maternal height was measured during the interview.…”