A molar pregnancy is also called a hydatidiform mole and it may be a form of pre-cancerous form of gestational trophoblastic disease. In a molar pregnancy, the cells that form the placenta (trophoblastic cells) develop abnormally and grow into a mass of cells instead of an embryo. These cells divide and grow in the uterus and are referred to as a mole, Latin for mass or lump.
Cause of molar pregnancies: When an egg with no genetic material is fertilized by a sperm it forms a complete mole. Placental tissues do not form in a complete mole, nor does the foetus develop. Instead, a mass of abnormal cell grows in the uterus. When a normal egg is fertilized by two sperms it forms an incomplete mole. In a partial molar pregnancy, placenta and foetus may partially develop, but never survive due to abnormality in the chromosomes.
Risk Factors of a molar pregnancy are advanced maternal age and a history of molar pregnancy.
Symptoms: Early symptoms of a molar pregnancy are the same as that of a normal pregnancy. But eventually symptoms like bleeding, severe nausea and vomiting, cramps and swelling of the abdomen show up. The bleeding may occur anytime between six to twenty weeks. Some women may develop pre-eclampsia before mid-pregnancy.
Diagnosis: Ultrasound helps doctor diagnose a molar pregnancy early these days. The ultrasound shows cysts that look like a cluster of grapes in the uterus. The hCG levels in a molar pregnancy are higher than normal which may lead to hyperthyroidism sometimes. Trophoblastic cell numbers are also higher than normal.
Treatment: Treatment of molar pregnancy is done by evacuating the uterus by uterine suction or by surgical D&C as soon as possible after the diagnosis. A chest x-ray is usually done to see if the abnormal cells from the pregnancy have spread to the lungs. The hCG levels are constantly monitored to make sure they decline, which mean that no abnormal cells remain in the body. The monitoring is done for a year or two even after the hCG levels have gone down to zero.
Conceiving after a molar pregnancy: Doctors advise waiting for a year after hCG levels have declined to zero before trying to conceive again. A molar pregnancy does not affect the fertility and it is possible to have a normal pregnancy after a molar pregnancy.