Objective: To calculate a population-based prospective risk of fetal death in monochorionic-diamniotic twins.
Study design: We evaluated 387 monochorionic-diamniotic twin pregnancies that were followed and delivered after 24 weeks in Slovenia during the period 1997-2007. Surveillance was not standardized. The prospective risk of fetal death was calculated as the total number of deaths after the beginning of the gestational period divided by the number of continuing pregnancies at or beyond that period.
Results: Fetal death rate was 32 of 774 fetuses (4.1%; 95% confidence interval (CI), 3.0%-5.9%); the prospective risk of stillbirth per pregnancy after 33 weeks of gestation was 6.2% (95% CI, 4.2%-9.1%).
Conclusion: The Slovenian population-based prospective risk of fetal death in monochorionic-diamniotic pregnancies that remained undelivered after 33 weeks' gestation is higher than previously reported from hospital-based studies.