Objective To determine the association between pre-gravid obesity and stillbirth. Methods A retrospective study of a population-based dataset of births at ≥34 weeks' gestation. We excluded fetal deaths due to lethal anomalies and intrapartum fetal deaths. We calculated the incidence of stillbirths, neonatal respiratory distress syndrome (RDS) and neonatal intensive care unit (NICU) admissions per ongoing pregnancies for each gestational week in the two body mass index (BMI) categories (≥30 vs.<30). Results Pre-pregnancy obesity (BMI≥30), pre-pregnancy diabetes, oligo- and polyhydramnios, being small for gestational age (SGA) and preeclampsia were significantly associated with stillbirth. However, the only pre-gravid factor that is amenable to intervention was obesity [adjusted odds ratio (OR) 2.0; 95% confidence interval (CI) 1.20, 3.3]. The rates of stillbirth seem to increase with gestational age in both BMI categories. RDS and NICU admission would be presented. Conclusion Birth near term might reduce stillbirths and decrease NICU admissions occurring in term and in post-term obese women. This presumable advantage might be offset by the potential risk of labor induction and cesarean section among obese women. Women of childbearing age with a BMI≥30 should be counseled about these risks of obesity during pregnancy and childbirth.
Keywords: admission to neonatal intensive care unit; neonatal respiratory distress syndrome; obesity; stillbirths.