7 Likely Reasons Your Miscarriage Ended in a Molar Pregnancy

molar pregnancy

A molar pregnancy is a rare and complicated condition that involves an abnormal placenta that carries no risk of viability to the fetus. It occurs when genetic material from the sperm or egg combine abnormally, creating a non-viable pregnancy as compared to a normal embryo with two sets of chromosomes. Most women who experience this will often miscarry naturally without intervention as there is no need for surgical removal.

In some cases, though, the body doesn’t remove itself from molar pregnancies properly and what was once thought to be a miscarriage turns out to be a persistent trophoblastic disease instead – one that puts both mother and baby at greater risk for serious complications. A molar pregnancy can turn into either choriocarcinoma or hydatidiform mole – both of which are commonly treated with a dilation and curettage procedure.

Here are some of the reasons Your Miscarriage Ended in a Molar Pregnancy

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1. Persistent trophoblastic disease

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This is why it’s so important for women to follow up with their physician after miscarriage. A dilation and curettage (D&C) procedure may be necessary if there are signs of persistent trophoblastic disease, which can happen even days or weeks later.

2. Infection

Abnormal tissues in the uterus can be a breeding ground for infection, creating more serious complications for both mother and baby than those caused by the molar pregnancy itself.

3. Maternal age

As women get older they are at greater risk for molar pregnancies because eggs aren’t as healthy as they once were when women were in their childbearing years.

4. Underlying medical condition

Some medical conditions such as diabetes and phenylketonuria (PKU) can make a woman more likely to experience molar pregnancies. Women diagnosed with chronic kidney disease, too, may be at risk for this type of miscarriage if their kidneys aren’t eliminating waste as they should be.

5. Abnormal ultrasound findings

An ultrasound that doesn’t find an embryo or fetus but does find placental tissue could signal the presence of a molar pregnancy. There are other possible causes, but it’s important to inform your doctor about any abnormal findings you notice on your ultrasounds so he or she knows what to look for during future visits.

6. Luteal phase defect

One of the reasons women have recurrent miscarriages is due to something called luteal phase defect, which is thought to be caused by a lack of progesterone. This condition can cause moles to form and continue attaching themselves to the uterine wall even after a miscarriage has occurred – potentially making it harder for women to conceive again in the future.

7. Chronic illnesses

Any chronic illness that causes poor immunity and inflammation could put a woman at risk of developing molar pregnancies. These include:

Systemic lupus erythematosus (SLE), ulcerative colitis, Crohn’s disease, celiac disease, and rheumatoid arthritis. In addition, those with HIV/AIDS are also more likely to experience molar pregnancies as well as thyroid disorders such as myxedema or Graves’ disease.


Miscarriages are an unfortunately common event for women early in pregnancy, but it’s important to remember that most of the time they are perfectly normal. It is vital that you follow up with your doctor after a miscarriage whether or not treatment is necessary.

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