In a molar pregnancy, the early placenta grows abnormally into a mass of cysts (called a hydatidiform mole). The embryo does not form at all or is malformed and cannot survive. About 1 in 1,500 pregnancies is molar.
An ultrasound exam can diagnose a molar pregnancy. The woman then has surgery to remove the molar tissue from the uterus. In some cases, molar tissue can turn into choriocarcinoma, a rare form of cancer. Fortunately, this cancer has a very high cure rate.
Most women with molar pregnancies go on to have healthy pregnancies later. The risk of reoccurrence is only about 1 to 2 percent.
What you can do:
Call your health care provider right away if you have any of these symptoms, especially around the tenth week of pregnancy:
- Vaginal bleeding, which may be dark brown in color
- Severe nausea and vomiting
- Rapid growth of the uterus
- High blood pressure
For more information, read the March of Dimes fact sheet Ectopic and Molar Pregnancy.
After a molar pregnancy, be sure to give yourself time to recover physically and to grieve the loss of your pregnancy. The March of Dimes provides information for grieving families.
August 2008