Prevention of intraventricular hemorrhage in very low birth weight infants by maternally administered phenobarbital.

One hundred fifty pregnant women destined to deliver infants less than 32 weeks were randomly assigned to two groups. One group received phenobarbital in doses sufficient to achieve blood levels of 15 to 40 micrograms/mL, and this level was maintained in the neonate after birth. The second group received no antenatal treatment, but the infants were treated with phenobarbital after birth for at least four days. The infants were followed with ultrasound examinations of the head on postnatal days 1, 4, and 10 to assess the grade and progression of intraventricular hemorrhage. Intraventricular hemorrhage was significantly less frequent in the experimental group, 16 of 75 (21%) versus 35 of 75 (47%), P less than .01. Similarly, the experimental group had significantly fewer cases of severe intraventricular hemorrhage (grades III and IV), four of 75 (5%) versus 15 of 75 (20%), P less than .05 and mortality three of 75 (4%) versus ten of 75 (13%), P less than .05. Maternally administered phenobarbital appears to be effective in reducing the incidence of intraventricular hemorrhage and lessening its severity.