Prospective risk of intrauterine death of monochorionic-diamniotic twins.

OBJECTIVE The purpose of this study was to calculate the prospective risk of fetal death in monochorionic-diamniotic twins. STUDY DESIGN We evaluated 193 monochorionic diamniotic twin pregnancies that were followed and delivered after 24 weeks. Surveillance included cardiotocography and sonography performed at least once weekly. The prospective risk of fetal death was calculated as the total number of deaths at the beginning of the gestational period divided by the number of continuing pregnancies at or beyond that period. RESULTS The fetal death rate was 5 of 193 pregnancies (2.6%; 95% CI, 1.1, 5.9); the prospective risk of stillbirth per pregnancy after 32 weeks of gestation was 1.2% (95% CI, 0.3% - 4.2%). CONCLUSION Under intensive surveillance, the prospective risk of fetal death in monochorionic-diamniotic pregnancies after 32 weeks of gestation is much lower than reported and does not support a policy of elective preterm delivery.