Rare Case Report: Coexistence of Complete Hydatidiform Mole and Normal Fetus in a Twin Pregnancy.

Background: The coexistence of a complete hydatidiform mole with a normal fetus in a twin pregnancy is a rare, high-risk obstetric condition with an extremely low incidence rate, presenting numerous clinical management challenges. The rarity of such cases, coupled with the scarcity of comprehensive literature, makes the successful management of this case a source of valuable experience and novel insights for clinical practice.

Case presentation: A 32-year-old patient conceived following a clomiphene-induced ovulation regimen. Mid-pregnancy ultrasound indicated a twin pregnancy (one viable fetus, the other consistent with the appearance of a complete hydatidiform mole), and the patient chose to continue the pregnancy. At 36+4 weeks of gestation, the patient was admitted for pregnancy-induced hypertension and underwent a cesarean section, delivering a healthy female infant and simultaneously removing the molar tissue. Postoperative pathological examination confirmed a complete hydatidiform mole with invasive lesions, which progressed to an invasive hydatidiform mole. The patient underwent seven cycles of methotrexate combination chemotherapy, with a follow-up period of three years showing no recurrence, ensuring the health of both mother and child.

Conclusion: Managing twin gestations involving a complete hydatidiform mole and a normal fetus necessitates a multidisciplinary approach, grounded in individualized assessment. The successful treatment of this case demonstrates that standardized diagnosis, close postoperative follow-up, and chemotherapy are crucial factors in improving maternal and fetal outcomes, offering significant clinical reference value.