Hydatidiform mole Health Article

Definition

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).

See also:

• Gestational trophoblastic disease
• Choriocarcinoma (a cancerous form of GTD)

Alternative Names

Hydatid mole; Molar pregnancy

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. Potential causes may include defects in the egg, problems within the uterus, or a diet low in protein, animal fat, and vitamin A. Women under age 16 or older than 40 have a higher risk for this condition. You also are more likely to have a molar pregnancy if you have had one in the past.

Symptoms

• Abnormal growth of the womb (uterus)
  • Excessive growth in about half of cases
  • Smaller-than-expected growth in about a third of cases
• Nausea and vomiting that may be severe enough to require a hospital stay
• Vaginal bleeding in pregnancy during the first 3 months of pregnancy
• Symptoms of hyperthyroidism
  • Heat intolerance
  • Loose stools
  • Rapid heart rate
  • Restlessness, nervousness
  • Skin warmer and more moist than usual
  • Trembling hands
  • Unexplained weight loss
• Symptoms similar to preeclampsia that occur in the 1st trimester or early 2nd trimester -- this is almost always a sign of a hydatidiform mole, because preeclampsia is extremely rare this early in a normal pregnancy
  • High blood pressure
  • Swelling in feet, ankles, legs