When do perinatal deaths in multiple pregnancies occur?

Perinatal mortality for multiple pregnancy remains at least 5 times the rate for singleton births. The major causes are neonatal deaths due to gross immaturity before 30 weeks' gestation, and stillbirths due to intrauterine growth retardation at all gestations, but especially after 32 weeks. Sixty four per cent of perinatal losses before 30 weeks' gestation occur before 26 weeks, highlighting the need to commence prophylactic measures earlier than usually recommended. The perinatal mortality in infants in multiple births weighing more than 2,500g is the same as that of singletons, but is 10 times this rate in multiple births weighing between 500g and 2,500g. Because the stillbirth rate in twins proceeding beyond 38 weeks' gestation is 3 times that of singleton births, elective termination of pregnancy is recommended if spontaneous labour has not occurred by this time.