Infants with birth weights less than 1,001 g. Survival, growth, and development.

Of 56 infants weighing less than 1,001 g who were born in 1980, 30 (54%) survived the neonatal period and 29 (52%) survived the first year. At 12 to 16 months of age, 44% of the measured survivors were below the fifth weight percentile and 32% were below the fifth head circumference percentile for their adjusted ages. Of the first-year survivors, 21 (72%) were developmentally normal, four (14%) were mildly handicapped, and four (14%) were moderately to severely handicapped at 12 to 34 months of age. Handicapped infants differed significantly from normal infants in their neonatal requirements for mechanical ventilation, but did not differ in birth weight, gestational age, route of delivery, Apgar scores, maternal age or marital status, maternal education or income, gender, race, place of birth, or proportions below the tenth percentile in weight or head circumference at birth.