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. To learn more about the Samsung RS85 Prestige ultrasound system, please visit:   https://www.bostonimaging.com/rs85-prestige-ultrasound-system-4 Click the YouTube Community tab or follow on social media for bonus teaching material posted throughout the week! Instagram: https://www.instagram.com/radiologistHQ/ Facebook: https://www.facebook.com/radiologistHeadQuarters/ Twitter: https://twitter.com/radiologistHQ