Hydatiform mole with coexisting live fetus in dichorionic twin gestation

A case of dichorionic twin pregnancy was diagnosed in a 29-year-old, on routine ultrasound at 12 weeks. Subsequent ultrasounds for persistent vaginal bleeding at 16 weeks revealed molar placenta with viable fetus in both gestational sacs. The patient declined any invasive prenatal testing to confirm the karyotype of the fetus. The pregnancy was managed expectantly until 21 weeks, when she had a spontaneous abortion of twin fetuses and separate placentae with attached molar tissue. A final karyotype on cord blood samples confirmed 46XY and 46XX for both fetuses. Histopathology of molar tissue reported complete mole, with diploid chromosomal pattern on subsequent DNA flow cytometry. The clinical, ultrasound and chromosomal examination suggest that there has been a quadruplet pregnancy where two embryos developed into normal fetuses and other two degenerated to complete moles.