Of 78 pregnancies after ovulation induced by menotropins and chorionic gonadotropin, 47 single, 23 twin, 5 triplet, 2 quadruplet, and 1 sextuplet births occurred. There was an abortion rate of 29% and a high multiple birth rate of 37.7% in patients who reached at least 20 weeks of pregnancy. The secondary sex ratio (M:F) in single births was 0.88; the sex ratio for births of twins was significantly lower (0.43). Only two of 23 twin births were male-male. The occurrence of multiple births probably caused the early delivery and corresponding fetal and neonatal loss of these infants (27%). The infants who died weighed less than 2,000 gm (4.4 lb) and were under 224 days gestation. Birth weight related to gestational age from day of ovulation was normal. The postnatal growth and development of the children were normal. The incidence of congenital malformations was within the normal range.