Intraventricular haemorrhage--timing of occurrence and relationship to perinatal events.

A total of 150 infants born at or before 34 weeks gestation had serial cranial ultrasound scans at age 8, 16, 24, 36, 48 h and 1 week. The overall incidence of IVH was 26%, but for infants less than 1500 g it was 51% and 50% of all haemorrhages were first detected in the first 8 h of life. Low-outlet forceps delivery and caesarean section offered some protection, but umbilical cord blood gas analysis did not support the hypothesis that hypoxia was causal. Respiratory distress and its complications were significantly associated with IVH. The more severe haemorrhages occurred in the less mature infants. The overall mortality in the study was 27% for the IVH group and 1.8% for the non-IVH group.