Effect of birth order on incidence of periventricular-intraventricular hemorrhage in very low birth weight twins.

The purpose of the study was to determine whether the incidence of periventricular-intraventricular hemorrhage (PV-IVH) is significantly different between the firstborn and secondborn of very low birth weight twins. The firstborn and secondborn of 102 sets of twins were compared by incidence of PV-IVH, mode of delivery, birth weight, 5-minute Apgar score, pH, duration of oxygen therapy, duration of ventilator support, and occurrence of patent ductus arteriosus, air leak, bronchopulmonary dysplasia, or hyaline membrane disease. PV-IVH was graded by the Papile classification. Statistical data were analyzed by either the paired t test or McNemar's test. Major PV-IVH (grades III and IV) occurred in 11 firstborn and 14 secondborn infants. Minor PV-IVH (grades I and II) occurred in 11 firstborn and 8 secondborn twins. Neither these findings nor those from other measured variables showed a statistically significant difference.