Cesarean scar pregnancies successfully treated with methotrexate.

Three cases of cesarean scar pregnancy successfully treated with methotrexate are described. The diagnosis was confirmed by transvaginal sonographic examinations showing a well-formed gestational sac in the myometrium of the lower uterine segment. Initial treatment with a systemic injection of 50 mg of methotrexate was not sufficient, and multiple doses were required to obtain a complete remission in two cases. In a case with a beta-hCG level of more than 20,000 mIU/mL with a viable embryo in a gestational sac, a combination of systemic and local treatment with methotrexate was required. It took 7-11 weeks for the beta-hCG level to become undetectable and 12-17 weeks for the cesarean scar pregnancy mass to disappear completely.