[Handicaps in twins and triplets].

This study was conducted to investigate the prevalence rates of handicaps in twins and triplets. The subjects were 252 twins and 287 triplets. The following results were obtained. 1) The prevalence rates of the handicapped were 8.7 per 100 triplets, and 4.4 per 100 twins. The risk of producing at least one handicapped child was approximately 22% in triplet pregnancy and 9% in twin pregnancy. This means that one in 4 or 5 sets of triplets had at least one handicapped child, as did one in 11 pairs of twins. 2) Cerebral palsy was the most frequent handicap in twins and triplets. The risks of producing a child with cerebral palsy were 2.0% and 3.1% in twins and triplets, respectively. 3) The prevalence rates of congenital anomalies (congenital heart disease, limb anomalies, and others) were 2.4% in twins and 4.5% in triplets. Approximately 45% of the handicaps in twins and triplets resulted from congenital anomalies. 4) The prevalence rate of the handicapped in twins and triplets was not associated with maternal age, but was associated with the years of delivery in triplets, and was higher in babies with shorter gestation periods.