Moderate to late preterm intrauterine growth restriction: A restrospective, observational study of the indications for delivery and outcomes in an Australian perinatal centre

Background: The management of preterm intrauterine growth restriction is limited to fetal surveillance and timely delivery. Despite the existence of evidence-based guidelines, uncertainty regarding the optimal timing of delivery is common, and management remains individualised for each patient. Aims: To provide recent Australian data on the indications for delivery of moderate to late preterm growth restricted infants and the outcomes of these deliveries. Materials and methods: Retrospective study of singleton live births delivered between 32 + 0 and 36 + 6 weeks gestation over a three-year period (2012–2014) at a Melbourne Metropolitan Hospital. ‘Small for gestational age’ (birthweight < 10th centile for gestation) identified intrauterine growth restricted infants. Indications for iatrogenic delivery were broadly categorised into maternal, fetal or pregnancy related. Obstetric and neonatal outcome variables were compared to other preterm infants using logistic regression. Results: Of the 146 (18.6%) small for gestational age infants born during the study period, 103 were iatrogenic deliveries, most commonly due to fetal indications (53.4%). Small for gestational age infants had higher odds of hypoglycaemia (adjusted odds ratio = 1.87, 95% CI: 1.23–2.84, P = 0.003) and jaundice (1.52, 1.01–2.28, P = 0.043) than their appropriately grown counterparts; however, there was no increase in the risk of serious morbidity or mortality. Conclusions: In this cohort, iatrogenic preterm delivery of small for gestational age infants between 32 + 0 and 36 + 6 weeks gestation was most commonly due to fetal indications and did not increase the risk of serious, short-term neonatal outcomes compared to their appropriately grown counterparts.