Preterm births in a resource constrained setting: sociobiologic risk factors and perinatal outcomes

Abstract

Background : To determine maternal risk factors and perinatal outcomes of preterm births in south-western Nigeria. Methods : A retrospective study of preterm and term deliveries in a tertiary hospital in Nigeria. The delivery records were reviewed and case files of preterm births were identified and retrieved. Perinatal outcomes were determined by review of the postnatal and special care baby unit records. Multivariate logistic regression was carried out to determine factors independently associated with preterm births. Adjusted odds ratios and confidence intervals were determined. Results : The preterm birth rate was 5.7%. Prelabour rupture of membranes was the leading cause of preterm birth, while a third of them were unexplainable. Age >35yrs (AOR 2.16(1.36-3.42)), the unbooked status (AOR 2.52(1.76-3.61)), Previous history of preterm delivery (AOR 6.41(2.48-16.60)), pre-labour rupture of membranes (AOR 11.08(6.01-18.56)), antepartum haemorrhage (AOR 10.91(4.94-24.09)), multiple gestations (AOR 32.23(13.07-79.50)) and hypertension in pregnancy(AOR6.42(3.79-10.88)) were independently associated with preterm delivery. Low birthweight, asphyxia, neonatal intensive care unit admission and perinatal mortality were common among preterm births. The perinatal mortality rate among the preterm neonates was 14.5%. Conclusion : Preterm birth remains a significant cause of perinatal deaths. Strategies addressing potentially modifiable risk factors will reduce the incidence and improve the perinatal outcomes associated with preterm births. Keywords : preterm delivery, prematurity, perinatal mortality, Nigeria.