In a molar pregnancy, the early placenta grows abnormally into a mass of cysts (called a hydatidiform mole). The baby (embryo) does not form at all or is malformed and cannot survive. Molar pregnancy is a threat to the pregnant woman because it can lead to heavy bleeding.
About 1 in 1,500 pregnancies is molar. Women who are over 40 or who have had two or more miscarriages are at increased risk of molar pregnancy.
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
- Abdominal cramping
After a molar pregnancy, make sure you give your self time to recover physically and to grieve the loss of your pregnancy. The March of Dimes provides information for grieving families.
March 2005






