A molar pregnancy occurs when an embryo is not able to fully form in the uterus. Instead, the tissue becomes a tumor. The term "molar" comes from the Greek word for "grapes" since many moles have a grape-like appearing tissue.
In the U.S., a molar pregnancy occurs in 1 out of every 2,000 pregnancies. In this condition, embryonic cells have an abnormal genetic makeup and form a tumor. This tumor, or "mole," can grow and even spread to other parts of a mother's body. In some cases, the mole may turn into a more dangerous cancer called choriocarcinoma.
Common symptoms of this condition may include: vaginal bleeding during pregnancy or shortly after a pregnancy, miscarriage, or abortionsevere nausea and vomiting, often bad enough to require treatment in the hospitala uterus that grows slower or faster than normal during pregnancysymptoms from an abnormally high level of thyroid hormone, also called hyperthyroidismhigh blood pressure that begins for the first time in the first trimester. This may mean that preeclampsia, also called toxemia of pregnancy, is present.symptoms of the tumor or cancer spreading to other organs. For example, coughing up blood may occur if the tumor goes to the lungs, or abdominal pain if the tumor goes to the liver.
In this condition, abnormal embryonic tissue inside a woman's uterus forms a tumor. The exact reason this occurs is not known. Common risk factors for this condition include: a recent full-term pregnancy, abortion, miscarriage, or ectopic pregnancya previous molar pregnancybeing of Asian or Mexican descentbeing younger than 20 or older than 40 years of agebeing poora diet that is low in protein, folate, or beta-carotene
Women are advised to get enough folate, carotene, and protein in their diet before becoming pregnant. This may decrease the risk of this condition.
Early diagnosis improves the chance of cure, though it cannot prevent this condition. Any woman with abnormal vaginal bleeding or other unusual symptoms after pregnancy should see her healthcare provider.
Diagnosis begins with a history and physical exam. There is usually a history of a recent pregnancy, whether or not a child was born.
A blood test is done to measure the level of HCG, the "hormone of pregnancy." In a molar pregnancy, the level of HCG becomes too high because of the abnormal tissue.
If the level of HCG is abnormally high, an ultrasound can help locate and confirm the tumor. A chest x-ray or MRI or CT scan of different parts of the body may be done if the healthcare provider suspects that the tumor has spread to other organs.
I n most cases, treatment results in a cure and there are few long-term effects. However, the tumor can spread to other areas of the body, which may result in organ damage and even death.
This condition is not contagious and poses no risk to others.
In most cases, the main treatment is a procedure called a dilation and curettage (D&C). This involves removing all the contents of the inside of the uterus with a special tool. In women who do not want any more children, a hysterectomy, or the removal of the uterus, may be advised.
If the tumor has spread to other areas of the body, chemotherapy and sometimes radiation therapy is usually advised.
If a hysterectomy or a D&C is done, the side effects may include bleeding, infection, and scarring of the uterus. Chemotherapy can cause stomach upset, nausea, weakness, and other side effects.
A woman is advised to take it easy for a few days after a D&C. A hysterectomy usually requires a few weeks of recovery. The woman should be alert for any unusual bleeding after surgery.
After all types of treatment, the level of HCG in the blood is checked regularly to make sure it returns to normal. If the level of HCG stays high or becomes high again in the future, this may mean that the tumor has spread or come back. Birth control should be used for at least 1 year after treatment. This is because pregnancy, by raising the level of HCG, can make it hard to detect if the tumor has come back.
Regular chest x-rays and pelvic exams are often advised. Any new or worsening symptoms should be reported to the healthcare provider.
Understanding Your Body, Felicia Stewart, Felicia Guest, Gary Stewart, and Robert Hatcher, 1987
Maternity and Gynecological Care, The Nurse and the Family, Irene Bobak, Margaret Jensen, Marianne Zalar, Mosby Co., 1989