Twin pregnancy in the right horn of a uterus didelphys: a case report.

A rare case of a twin pregnancy occurring in the right horn of a uterus didelphys (double uterus, double cervix and septate vagina) is reported. The occasional diagnosis of this uterine anomaly was made after the pregnancy was detected. Both embryos, with cardiac actions which proved the viability of the gestation from the very early stage of pregnancy, were detected by transvaginal ultrasonography. Two male infants were delivered by Cesarean section in the 34th week. The importance of the transvaginal sonography and the handling of the case during this high-risk pregnancy are reported.