Early ultrasound diagnosis and follow-up of molar pregnancies.

The objective of this study was to investigate the role of ultrasound in the differential diagnosis and management of early pregnancies presenting with placental molar changes. Placental features were recorded over a 10-month period in women undergoing ultrasound examination at 10-14 weeks of gestation. In cases of a molar pregnancy, the fetal karyotype was obtained in utero and, if the pregnancy continued, the maternal concentration of human chorionic gonadotropin (hCG) and uterine artery resistance to flow were measured serially. A histopathological examination of the placenta was performed in all cases after delivery. During the study period, 9425 women had an early scan and 11 molar pregnancies were identified including one classical mole, four hydatidiform moles coexisting with a normal pregnancy, three partial triploid moles and three partial moles associated in one case with a fetus presenting congenitial anomalies diagnostic of Beckwith-Wiedemann syndrome. The hCG levels were high in all cases except one case of triploidy and remained high during the rest of the pregnancy in cases of hydatidiform moles coexisting with a fetus. In these cases, the uterine artery resistance was normal. The present data indicate that placental ultrasound examination can correctly identify molar changes in early pregnancy and together with hCG level and uterine Doppler measurements can establish the differential diagnosis in utero of the various forms of placental molar transformations.