Condition Basics

What is a molar pregnancy?

A molar pregnancy means that tissue that normally becomes a fetus instead becomes an abnormal growth in your uterus. Even though it isn't an embryo, this growth triggers symptoms of pregnancy.

This tissue can cause serious problems in some cases. So a molar pregnancy should be treated right away. Treatment will make sure that all of the tissue is removed.

What causes it?

Molar pregnancy is thought to be caused by a problem with the genetic information of an egg or sperm. There are two types of molar pregnancy: complete and partial.

• Complete molar pregnancy. An egg with no genetic information is fertilized by a sperm. It does not develop into a fetus. It continues to grow as a lump of abnormal tissue that looks a bit like a cluster of grapes and can fill the uterus.
• Partial molar pregnancy. An egg is fertilized by two sperm. The placenta becomes the molar growth. Any fetal tissue that forms is likely to have severe defects.

Sometimes a pregnancy that seems to be twins is found to be one fetus and one molar pregnancy. But this is very rare.

Things that may increase your risk of having a molar pregnancy include:

• Age. The risk for complete molar pregnancy steadily increases after age 35.
• A history of molar pregnancy, especially if you've had two or more.
• A history of miscarriage.
• A diet low in carotene. Carotene is a form of vitamin A.

What are the symptoms?

A molar pregnancy causes the same early symptoms that a normal pregnancy does, such as a missed period or morning sickness. But a molar pregnancy usually causes other symptoms too. These may include:

• Bleeding from the vagina.
• A uterus that is larger than normal.
• Severe nausea and vomiting.
• Signs of hyperthyroidism. These include feeling nervous or tired, having a fast or irregular heartbeat, and sweating a lot.
• An uncomfortable feeling in the pelvis.
• Vaginal discharge of tissue that is shaped like grapes. This is usually a sign of molar pregnancy.

Most of these symptoms can also occur with a normal pregnancy, a multiple pregnancy, or a miscarriage.

How is it diagnosed?

Your doctor can find a molar pregnancy with:

• A blood test to measure your pregnancy hormones.
• A pelvic ultrasound.

Your doctor can also find a molar pregnancy during a routine ultrasound in early pregnancy. Partial molar pregnancies are often found during treatment for an incomplete miscarriage.

How is a molar pregnancy treated?

When you have a molar pregnancy, you need treatment right away to remove all of the growth from your uterus. The growth is removed with a procedure called vacuum aspiration.

If you don't want a future pregnancy, you may decide to have your uterus removed (hysterectomy) instead of having a vacuum aspiration to treat your molar pregnancy.

After treatment, you will have regular blood tests to look for signs of trophoblastic disease. These blood tests may be done over the next 6 to 12 months. If you still have your uterus, you will need to use birth control during this time so you don't get pregnant. It's very important to see your doctor for all follow-up visits.

If you do get trophoblastic disease, there's a small chance that it will turn into cancer. But your doctor will likely find it early so it can be cured with chemotherapy. In the rare case when the cancer has had time to spread to other parts of the body, more chemotherapy is needed, sometimes combined with radiation treatment. If you've had trophoblastic disease, it's likely you'll be able to get pregnant later.

After a molar pregnancy, you may feel many different emotions. It may help to find a local support group or talk to your friends, a counsellor, or a spiritual advisor.

How can you care for yourself?

• Take your medicines exactly as prescribed. Call your doctor or nurse advice line if you think you are having a problem with your medicine.
• You may have vaginal bleeding that's similar to a period. It may last for up to 10 days. Use sanitary pads until you stop bleeding. Using pads makes it easier to keep track of your bleeding. You may use tampons during your next period. It should start in 3 to 6 weeks.
• Ask your doctor when it is okay for you to have sex.
• Take an over-the-counter pain medicine, such as acetaminophen (Tylenol), ibuprofen (Advil, Motrin), or naproxen (Aleve), to relieve pain or cramping. Read and follow all instructions on the label. Do not take two or more pain medicines at the same time unless the doctor told you to. Many pain medicines have acetaminophen, which is Tylenol. Too much acetaminophen (Tylenol) can be harmful.
• Get plenty of rest. You may be more tired than normal for a few weeks.
• Take it easy. Do not exercise too much or lift heavy objects (more than 9 kilograms [20 pounds]) until your doctor tells you it is safe to do your normal activities.
• Pay attention to your feelings. If you're sad and it's not getting any easier, talk with your doctor or a counsellor.
• Talk to your doctor if you are worried about having children in the future.
• Most doctors suggest waiting for 6 to 12 months before trying to get pregnant. Ask your doctor about birth control. Without birth control, you might get pregnant before your next period starts.