The neonatal respiratory morbidity associated with early term caesarean section - an emerging pandemic.

Objectives: To examine the impact of early term caesarean section (CS) on respiratory morbidity and early neonatal outcomes when elective caesarean section was carried out before 39 completed weeks gestation in our population.

Methods: A one-year population-based retrospective cohort analysis using routinely collected hospital data. Livebirths from women who had elective lower segment cesarean section (ELSCS) for uncomplicated singleton pregnancies at early term (ET) 37+0 to 38+6 weeks were compared to full term (FT)≥39+0 weeks gestation. Exclusion criteria included diabetes, antenatal corticosteroid use, stillbirths, immediate neonatal deaths, normal vaginal deliveries and emergency caesareans sections. The outcomes were combined respiratory morbidity (tachypnea [TTN] and respiratory distress syndrome [RDS]), Apgar <7 at 5 min of age, respiratory support, duration of respiratory support and NICU admission.

Results: Out of a total of 1,466 elective CS with term livebirths, the timing of CS was early term (ET) n=758 (52%) and full term (FT) n=708 (48%). There was a higher incidence of respiratory morbidities and neonatal outcomes in the ET in comparison to FT newborns. In the univariable analysis, significant risks for outcomes were: the need for oxygen support OR 2.42 (95% C.I. 1.38-4.22), respiratory distress syndrome and/or transient tachypnea of newborn (RDSF/TTN) OR 2.44 (95% C.I. 1.33-4.47) and neonatal intensive care unit (NICU) admission OR 1.91 (95% C.I. 1.22-2.98). Only the need for oxygen support remained (OR 1.81, 95% C.I. 1.0-3.26) in the multivariable analysis. These results were observed within the context of a significantly higher proportion of older, multiparous, and higher number of previous caesarean sections in the early term CS group.

Conclusions: There is a significant risk of respiratory morbidities in infants born by elective cesarean section prior to full term gestation. Obstetricians should aim towards reducing the high rate of women with previous multiple cesarean sections including balancing the obstetric indication of early delivery among such women with the evident risk of neonatal respiratory morbidity.