Twin pregnancy: prematurity and perinatal mortality.

An 8-year (1976-1984) retrospective analysis was undertaken of the management and outcome of 245 twin pregnancies delivered at Flinders Medical Centre, Adelaide. The incidence of twin delivery was 1 in 69 with a perinatal mortality of 85.7 per 1,000 total births. Amongst 42 perinatal deaths, 28 were associated with preterm labour at or before 28 weeks' gestation. If bed rest in hospital is to be implemented as a possible means of improving perinatal outcome in twin pregnancy it needs to be effected between 21 and 28 weeks' gestation; there is no rational theoretical basis for hospitalization beyond this time.