While it is not rare, a molar pregnancy is a somewhat uncommon occurrence. Although it can technically happen to any women, pregnant women over the age of 40, as well as those women who have previously experienced a molar pregnancy, are more at risk.
Types of Molar Pregnancies
Generally, there are two different types of molar pregnancies a woman may experience: a complete and an incomplete molar pregnancy. A complete molar pregnancy refers to a pregnancy that develops a placenta but no fetus. In complete molar pregnancies, the egg’s nucleus is either missing or inactivated resulting in a lack of genetic information causing the fertilizing sperm to duplicate itself. Because of the lopsided genetic information, the developing pregnancy will lack a fetus, although the placenta will still form and hCG hormone will still be produced. Complete molar pregnancies also cause the uterus to quickly grow, leading to bleeding in the uterine cavity or vaginal bleeding.
A partial molar pregnancy is much more common than a complete molar pregnancy. In this instance, an egg is fertilized by two separate sperms, which would normally result in a twin pregnancy. However, in a partial mole pregnancy, the fertilized egg ends up with too many chromosomes leading to an abnormal fetus and placenta. Due to the improper development, the fetus almost always dies in the uterus.
Signs and Symptoms of a Molar Pregnancy
If you’re pregnant, or think you may be, and display any of these symptoms, make an appointment with your health care provider.
- Severe nausea and vomiting
- Vaginal bleeding (usually dark brown in color)
- Abdominal cramps
- Unable to detect fetal movement or heartbeat
- Abnormally high or low hCG levels
- An ultrasound displaying grape-like clusters in the ovaries or a "snowstorm" effect
Treating Molar Pregnancies
In many cases, a molar pregnancy will spontaneously end on its own, usually with the passing of a grape-like mass. However, in some cases it will be necessary for suction and curettage to be performed. This is when a suction vacuum is used to gently remove the products of the molar pregnancy. If the mole has been extensive, a hysterectomy may be performed but only if the woman is done having children.
After treatment, it will be necessary for a woman to have her hCG levels monitored weekly until they return to zero at which point monthly hCG level monitoring will be required for a year. The reason for this is that molar pregnancies can return and turn into a type of cancer. Women who have a molar pregnancy are also asked to wait at least a year before trying to become pregnant again.
Preventing molar pregnancies may be possible. There is some evidence to suggest that a lack of protein may cause molar pregnancies as can ovulation deficiencies. Increasing your intake of vitamin A as well as protein derived from animal sources may help reduce your risk of a molar pregnancy.
Pregnancy After a Molar Pregnancy
Although women are required to wait at least a year before getting pregnant again, the chances of experiencing another molar pregnancy are slim. Only about one to two per cent of women will go through another molar pregnancy. However, it is recommended that women with a previous molar pregnancy speak with a genetic counselor prior to trying to conceive again.