Low Risk of Relapse After Achieving Undetectable hCG Levels in Women With Partial Molar Pregnancy

Abstract
We evaluated the risk of gestational trophoblastic neoplasia (GTN) for women with partial molar pregnancy whose human chorionic gonadotropin (hCG) levels fall spontaneously to undetectable levels using a sensitive hCG assay. We analyzed data from the New England Trophoblastic Disease Center to estimate the risk of GTN among 284 women with partial molar pregnancy and at least 6 months of gonadotropin follow-up. None of the 238 women with complete gonadotropin follow-up and a spontaneous decline in serum hCG levels to undetectable levels subsequently developed GTN (95% confidence interval 0-1.6%). If these results are replicated at other institutions with longstanding experience managing partial molar pregnancies, it may be reasonable to abbreviate clinical follow-up for women with partial molar pregnancy whose serum hCG levels spontaneously decline to an undetectable level.