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Hydatidiform mole: Epidemiology, clinical features, and diagnosis

Ross S Berkowitz, MD
Donald Peter Goldstein, MD
Neil S Horowitz, MD
Section Editor
Barbara Goff, MD
Deputy Editor
Sandy J Falk, MD, FACOG


Hydatidiform mole (HM) was first described by Hippocrates around 400 B.C. as "dropsy of the uterus." Since that time, HM (also referred to as molar pregnancy or mole) has been of clinical and research interest. Molar pregnancy is part of a group of diseases classified as gestational trophoblastic disease (GTD), which originate in the placenta and have the potential to locally invade the uterus and metastasize. The pathogenesis of GTD is unique because the maternal tumor arises from gestational rather than maternal tissue [1].

HM is made up of two distinct entities, complete hydatidiform mole and partial hydatidiform mole. These differ on the basis of chromosomal pattern, gross and microscopic histopathology, clinical presentation, and outcome [2-4]. Molar pregnancies, although benign, are considered to be premalignant because they have the potential to develop into a malignancy. Malignant disease is referred to as gestational trophoblastic neoplasia (GTN); the histologic entities included in this group are:

Invasive mole


Placental site trophoblastic tumor

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Literature review current through: Nov 2017. | This topic last updated: Apr 14, 2017.
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