How is incidence of hydatidiform mole?

➢ The incidence of complete hydatidiform mole is about 1 to 1.5 per 2000 pregnancies in the United States and other Western countries. ➢ For unknown reasons, the incidence is much higher in Asian countries. ➢ Moles are most common before the age of 20 and after the age of 40 years, and a history of the condition increases the risk for molar disease in subsequent pregnancies. ➢ Although molar disease formerly was discovered at 12 to 14 weeks of pregnancy during investigation for a gestation that was “too large for dates,” early monitoring of pregnancies by ultrasound has lowered the gestational age at detection. ➢ In both complete and partial moles, elevation of hCG in the maternal blood and absence of fetal heart sounds are typical.