Low birthweight and perinatal mortality in Lagos.

A detailed retrospective analysis was made of the records of 693 singleton low birthweight babies who accounted for 5.2% of all births during 1973-77. The corrected perinatal mortality (PNM) in low birthweight was 339/1000 total singleton births, 43.5% of all perinatal deaths. The clinical cause of LBW was unknown in 66% of the cases. 60.5% of the LBW babies were premature while 39.5% were intrauterine growth retarded (IUGR) babies. The corrected PNM in the IUGR group was 62/1000 while in the preterm group, it was 520/1000. 1/2 of all preterm deliveries were due to unknown causes. Antepartum hemorrhage (21.7%) was the main cause of preterm delivery followed by the pregnancy induced hypertension (17.7%). There were statistically significant differences in the stillbirth rates and early neonatal mortality rates of the premature (unknown cause) and premature (known clinical causes). Preterm births accounted for 98.6% of the early neonatal deaths in LBW. Survival rates were poorest in premature breech deliveries.