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Hydatidiform mole - Overview

Alternative Names

Hydatid mole; Molar pregnancy

Definition of Hydatidiform mole:

A hydatidiform mole is a rare mass or growth that forms inside the uterus at the beginning of a pregnancy. It is a type of gestational trophoblastic disease (GTD).

Causes, incidence, and risk factors:

A hydatidiform mole, or molar pregnancy, results from over-production of the tissue that is supposed to develop into the placenta. The placenta normally feeds a fetus during pregnancy. In this condition, the tissues develop into an abnormal growth, called a mass.

There are two types:

Partial molar pregnancy
Complete molar pregnancy

A partial molar pregnancy means there is an abnormal placenta and some fetal development.

In a complete molar pregnancy, there is an abnormal placenta but no fetus.

Both forms are due to problems during fertilization. The exact cause of fertilization problems are unknown. However, a diet low in protein, animal fat, and vitamin A may play a role.

Uterus

Normal uterine anatomy (cut section)

Reviewed last on: 11/21/2010
Linda J. Vorvick, MD, Medical Director, MEDEX Northwest Division of Physician Assistant Studies, University of Washington, School of Medicine; Susan Storck, MD, FACOG, Chief, Eastside Department of Obstetrics and Gynecology, Group Health Cooperative of Puget Sound, Redmond, Washington; Clinical Teaching Faculty, Department of Obstetrics and Gynecology, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

References

Kavanagh JJ, Gershenson DM. Gestational trophoblastic disease: hydatidiform mole, nonmetastatic and metastatic gestational trophoblastic tumor: diagnosis and management. In: Katz VL, Lentz GM, Lobo RA, Gershenson DM, eds. Comprehensive Gynecology. 5th ed. Philadelphia, Pa: Mosby Elsevier; 2007:chap 35.

Copeland LJ, Landon MB. Malignant diseases and pregnancy. In: Gabbe SG, Niebyl JR, Simpson JL, eds. Obstetrics - Normal and Problem Pregnancies. 5th ed. Philadelphia, Pa: Elsevier Churchill Livingstone; 2007:chap 45.

Goldstein DP, Berkowitz RS. Gestational trophoblastic disease. In: Abeloff MD, Armitage JO, Niederhuber JE, Kastan MB, McKenna WG, eds. Abeloff’s Clinical Oncology. 4th ed. Philadelphia, Pa: Elsevier Churchill Livingstone; 2008:chap 94.

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