Ultrasound of Complete Molar Pregnancy

In this radiology lecture, the ultrasound appearance of complete molar pregnancy is revealed.

Key points include:

AKA hydatiform mole = Most common form of gestational trophoblastic disease.
Gestational trophoblastic neoplasia (GTN) less common = Invasive mole and choriocarcinoma.
Approximately 1/1,000 pregnancies is a molar pregnancy.
Most common in females under age 20 and over age 35.
Two types of molar pregnancy: Complete (most common) and partial.
Complete: Diploid (paternal DNA only), no fetus, more likely to be complicated by GTN.
Partial: Triploid (maternal and paternal DNA), abnormal fetus or fetal parts, harder to diagnose.
Complete hydatiform mole presentation: Vaginal bleeding, enlarged uterus inconsistent with dates, hyperemesis. Markedly elevated β-hCG level (variable for partial molar pregnancies).
Large theca lutein cysts due to ovarian stimulation from elevated β-hCG, but uncommon.
US: Heterogeneous, echogenic mass (“snowstorm” appearance), small anechoic cystic spaces (“cluster of grapes”) = hydropic chorionic villi.
Treatment: Dilation & curettage. β-hCG levels monitored until no longer detectable to confirm no residual disease.