Hydatidiform Mole (Molar Pregnancy)

What is a hydatidiform mole?

A hydatidiform mole also known as a molar pregnancy is a rare condition, where there is an abnormal development of cells that form a grape like mass inside the uterus (womb). This abnormal development takes place around the fertilized egg thereby preventing a placenta from forming or the pregnancy to becom viable. In simple terms, hydatidiform mole represents a false pregnancy which symbolizes abnormal development of the womb with no live fetus. This disease belongs to the category of gestational trophoblastic disorder (GTD).

Molar pregnancy happens due to inability of the chorionic villi to develop normally. Chorionic villi are small hair like projections that attach the placenta to the uterus. The villi do not develop properly and grow as watery clusters that are insufficient to provide life support to the developing fetus. In the United States Hydatidiform mole occurs at the rate of about 1 in every 1,500 pregnancies. The rate of incidence is higher in Asian countries affecting about 1 in 200 pregnancies. Younger women aged below 20 years and older aged 45 years and above are more susceptible to get molar pregnancy.

Hydatidiform Mole Process

There are two types of molar pregnancy: partial and complete. A partial molar pregnancy will have an underdeveloped embryo that fails to thrive. A complete molar pregnancy has no embryo but instead there is a small cluster of cells that resembles water-filled pouches. This condition is diagnosed later during the third month when there is vaginal spotting which is meager in the beginning but later on there is heavy bleeding accompanied by abdominal cramps. The disease process in the development of a hydatidiform mole depends on a variety of factors.

Age at conception

The age of a pregnant women has a link to development of hydatidiform mole. If the pregnant woman is less than 20 years or is 40 years and above then there are greater chances of molar pregnancy.

Nutritional deficiencies

A diet low in protein and folic acid can lead to abnormal fetal development. Due to poor nutrition, the fetus fails to thrive and a miscarriage occurs. As a result, a hydatidiform mole can occur.

Previous history of miscarriage

If pregnant women have suffered 2 to 3 miscarriages then the chances of developing molar pregnancy are higher. This may occur because hydatidiform moles develop from the cells that remain in the uterus after the miscarriage has occurred.

Hydatidiform Mole Causes

The underlying cause behind the occurrence of hydatidiform mole is unclear and not very well understood. The following factors may increase the risk :

  • Poor nutrition – a diet low in proteins and folic acid
  • Miscarriage
  • Abnormalities in the uterus
  • Defects in the ova
  • Swelling of chorionic villi

Hydatidiform Mole Symptoms

Women with a hydatidiform mole experience excessive and rapid growth of the uterus during the first trimester. The symptoms include

  • Severe nausea and vomiting
  • Vaginal bleeding during the first 3 months of pregnancy
  • Rapid heart rate
  • High blood pressure
  • Diarrhea
  • Intolerance to heat
  • Restlessness
  • Trembling hands and feet
  • Swelling of the feet, hands and ankles
  • Weakness
  • Dehydration
  • Weight loss
  • Skin in warm and moist
  • Hyperthyroidism
  • Preeclampsia during the first and second trimester

Hydatidiform Mole Diagnosis

A pelvic examination is carried out which gives a clear picture about the size of the womb and also give accurate results on the sound of fetal heart beat. In case of a hydatidiform mole, the size of the womb is abnormally large and fetal heart beat absent. Pelvic examination will also show signs of vaginal bleeding. Ultrasound will be carried out to see the presence or absence of placenta.

In addition other tests that are required for diagnosing hydatidiform mole include:

  • Complete blood count
  • Blood clotting tests
  • HCG blood test to determine the levels of the hormone which can be produced in excess in case of molar pregnancy
  • X-ray of the chest
  • CT scan or MRI of the abdomen for presence of any abnormal lumps in the uterus
  • Liver and kidney function tests

Hydatidiform Mole Complications

Several complications that accompany hydatidiform mole consists of :

  • Lung disorders due to increase in size of uterus
  • Thyroid disease
  • Preeclampsia

Hydatidiform Mole Treatment

Treatment of hydatidiform mole involves removal of the grape-like mass either through surgery or with the use of certain drugs. It is needs to be understood that complete removal of the mole is necessary to rule out any possibility of re-growth of the tissue if it is cancerous. In many cases the human body removes the tissue naturally by the fourth month. Instances where the body fails to do so, the tissue is removed with the help of medication such as oxytocin which stimulates uterine contractions.

A D&C (dilation and curettage) may be necessary. In this procedure the woman is kept under anesthesia and the cervix is widened to enable the removal of the contents of the uterus through suction. Once this is done, a final scrapping is also carried out to ensure complete removal of the mole.

After carrying out any of the above mentioned procedures, the patient needs to be monitored for a minimum of 2 months as there is a risk of the mole becoming cancerous. If the tissue is cancerous in nature then chemotherapy needs to be initiated with subsequent removal of the tissue. In addition to this, radiation therapy may also be needed in order to prevent the cancer from spreading to other parts of the body. The mode of treatment will depend on the extent of spread of the cancer.

More Related Topics