Do very sick neonates born at term have antenatal risks? 2. Infants ventilated primarily for lung disease

Aims. 1. Ascertain antenatal and intrapartum risk factors for term neonates ventilated primarily for respiratory problems. 2. Describe the neonatal mo rbidity and mortality. Methods. Population-based case control cohort study. Setting. Sydney and four large rural/urban Health Areas in New South Wales, 1996. Subjects. Singleton term infants, no major congenital anomaly: subset of 99 infants ventilated primarily for respiratory problems from 182 cases admit ted to a tertiary neonatal intensive care unit (NICU) for mechanical ventil ation, and 550 randomly selected controls. Outcome. Risk factors for case status by maternal, antenatal, labor, delive ry, and combined epochs, adjusted Odds Ratios (OR), 95 per cent Confidence Intervals (CI), p<0.05. Results. Predictors of case status by multivariate epochs: mother's age <gr eater than or equal to>35 years (1.9 (1.1, 3.2) p=0.03), primigravida (1.8 (1.1, 2.8) p=0.01), any antenatal complication (3.8 (2.4, 5.9) p=0.0001), b irth weight <3rd percentile (3.7 (1.5, 9.1) p=0.006), gestational diabetes (2.9 (1.3, 6.9) p=0.01), maternal pyrexia (6.5 (1.6, 27.2) p=0.01), birth w eight >90th percentile (1.8 (1.01, 3.2) p=0.047), gestation 37-38 weeks (2. 3 (1.5, 3.6) p=0.0004), forceps (4.4 (2. 1, 9.1) p=0.0001), elective cesare an section (3.7 (2.0, 6.5)p=0.0001), emergency cesarean section (4.5 (2.4, 8.4) p=0.0001). Case mortality rate was 5 per cent. Conclusion. The pathways to neonatal respiratory morbidity in term infants are multifactorial. Several areas which warrant more in-depth study are: el ective cesarean section at 37-38 weeks gestation, fetal growth restriction, macrosomia and the pattern of in-utero growth, maternal weight gain during pregnancy, gestational diabetes, pyrexia in labor and the role of chorioam nionitis.