Preterm birth in rural Malawi: high incidence in ultrasound-dated population

Abstract

Preterm birth is the major cause of neonatal death, and has an incidence in industrialized countries of 7%. We have found a high incidence (25-30%) previously in a population of anaemic, pregnant women in southern Malawi, studied with ultrasound dating. Cohort study of 512 unselected pregnant women in rural communities in Malawi. All had ultrasound fetal measurements before 24 weeks. 20.3% of women delivered before 37 completed weeks of pregnancy. Babies born before 37 completed weeks but after 32 weeks (16%) were twice as likely to die as babies born at term (6.9 versus 3.4%) but this difference did not achieve statistical significance. For those born between 24 and 33 weeks gestation (4.4%) there was a highly significant increase in perinatal mortality (75%) (p <0 .000001). This population has a very high rate of preterm birth, which is probably infection-related. It may be representative of many rural populations in sub-Saharan Africa. Tackling the problem of neonatal mortality in low income countries will require effective methods to prevent preterm birth.