Obstetrical determinants of neonatal neurological morbidity in <= 1000-gram infants

The purpose of this study is to identify obstetrical factors associated wit h adverse neurological outcome in less than or equal to 1000-g infants. In al-year (1992-1993) observational study, the NICHD MFMU Network collected o bstetrical risk factors for 486 infants who weighed less than or equal to 1 000 g at birth and who survived > 2 days. Infants' records were abstracted for seizures, intraventricular hemorrhage, and an abnormal neurological eva luation. Seventy-nine (16%) infants had a Grade III or IV intraventricular hemorrhage, 46 (9%) developed seizures and 57 (14%) had an abnormal neurolo gical evaluation. Both lower birth weight and earlier gestational age corre lated (P <0.01) with an increasing incidence of all three outcomes. Several other factors appeared to be associated with neurological morbidity, howev er, after controlling for potential confounders in the multivariate analyse s, most of these factors were no longer significant. African-American race, odds ratio (OR) 0.6 (0.3-1.0), and severe preeclampsia, OR 0.2 (0.1-0.7), were protective against intraventricular hemorrhage. Maternal treatment wit h corticosteroids did not impact neurological outcome in this study populat ion. We conclude that, in a population of less than or equal to 1000-g infa nts, lower birth weight and earlier gestational age were the only consisten tly significant predictors of all three adverse neurological outcomes.