An Incidental Ultrasonographic Diagnosis of Partial Hydatidiform Mole in a Old Primigravida: A Case Report

Hydatidiform mole is an abnormal pregnancy common in Asian populations compared to western countries; however, a partial hydatidiform mole is relatively uncommon and very challenging to diagnose on ultrasound. We reported a 24 years old female visited our clinic whose first antenatal visit was regular with normal viable fetus on ultrasonographic scan. However, an uneventful scan at 12 weeks period of gestation revealed a large irregular gestational sac with the disproportionately small embryo corresponding to 6(+6) weeks with no cardiac activity. Additionally, there was markedly thickened placenta measuring 30mm in thickness without cystic spaces within the placenta. Further, her beta-human chorionic gonadotrophin level was very high and suction evacuation sample showed hydropic chorionic villi lined by trophoblastic cells with cistern formation and scalloped border. In conclusion, partial hydatidiform mole is an uncommon molar pregnancy rarely diagnose on ultrasonography. Late first-trimester scan and excessively high beta-human chorionic gonadotrophin levels confirm the diagnosis.