Four hundred and thirty-four twins delivered from 220 women at Notre-Dame Hospital were studied during a period of 11 years (1969–1979). The maternal, fetal, and neonatal outcome was compared before and after 1974, the year ultrasonography and other changes in perinatal care were introduced in our institution. Early diagnosis occurred more frequently after 1974, together with increased antenatal hospitalization. Preeclampsia and hepatic cholestasis occurred in 19.5% and 9.5% of women, respectively. Preterm delivery occurred in 42.2% of the cases. The corrected fetal mortality rate was 30.2/1,000 and corrected perinatal mortality rate was 74.9/1,000. About 90% of the neonatal deaths occurred in infants born before 36 weeks. Internal version and complete extraction of the second twin increased the neonatal mortality sixfold compared to spontaneous delivery. Availability of ultrasound examination significantly reduced preterm delivery.
