Superfetation in uterus pseudo didelphys: an unreported event.

A 20-year-old primigravida initially diagnosed at 28 weeks to have superfetation in a case of a bicornuate uterus was subsequently found to have uterus pseudo didelphys during a cesarean section at 35 weeks. This type of uterine anomaly with twin gestation has been previously reported in five case reports, but superfetation with such müllerian abnormality has not been previously described.