Improved neurodevelopmental outcomes for extremely low birth weight infants in 2000-2002

BACKGROUND. Neurodevelopmental impairment of extremely low birth weight infants increased in the 1990s. Modern therapeutic changes may have influenced more recent neonatal outcomes. OBJECTIVE. We sought to compare neonatal therapies and outcomes among all extremely low birth weight infants born in 2000 - 2002 (period III) to 2 previous periods: 1982 - 1989 (period I) and 1990 - 1999 (period II). METHODS. The population included 496 extremely low birth weight infants born at our perinatal center during period I, 749 during period II, and 233 during period III. Therapies, rates of death, and survival with and without impairment at 20 months' corrected age were compared. RESULTS. Between periods I and II, survival increased from 49% to 68% as did neonatal morbidity. This resulted in increased survival without impairment but also increased survival with impairment. Changes in therapy during period III included an increase in antenatal steroid use and a decrease in postnatal steroid use, although the rate of chronic lung disease did not change. Sepsis decreased, as did severe intraventricular hemorrhage. On follow-up, the rate of cerebral palsy decreased from 13% to 5%, resulting in a decrease in neurodevelopmental impairment from 35% to 23%. As a result, during period III versus II, survival without impairment increased, whereas survival with impairment decreased. CONCLUSION. Since 2000, neurodevelopmental impairment has decreased among extremely low birth weight infants. A variety of perinatal and neonatal factors were associated with the improved outcomes including increased antenatal steroid use and cesarean section delivery, as well as decreased sepsis, severe cranial ultrasound abnormalities, and postnatal steroid use despite no change in the rate of chronic lung disease.