Complete hydatidiform mole with coexistent fetus

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Complete hydatidiform mole with coexistent fetus (CHMCF) is an extremely rare entity whereas the name suggests there is a twin pregnancy with a complete hydatidiform mole and a normal fetus.

Epidemiology

It is seen extremely rarely, with an estimated incidence of one in 22,000–100,000 pregnancies.

Clinical features

Exaggerated signs and symptoms of pregnancy may be evident. The uterus is larger than the period of gestation and abnormally high levels of hCG. Clinical problems include vaginal bleeding, toxemia and excessive vomiting.

Radiographic features

Ultrasound

Sonological findings of a complete hydatidiform mole, such as a snowstorm appearance are seen with a completely normal fetus with a normal placenta.

Treatment and prognosis

These cases are at high risk of spontaneous abortion, preterm delivery, intrauterine fetal death, bleeding, preeclampsia and persistent trophoblastic disease (PTD).

Considering the maternal complication, termination of pregnancy is suggested by a large number of studies. Some suggest that after confirmation of normal karyotype in the coexistent fetus and appropriate patient counseling, continuation of pregnancy can be attempted despite a 30% risk of bleeding and preeclampsia.

Differential diagnosis

Possible differential considerations include