A molar pregnancy can be a distressing pregnancy complication. It occurs rarely—approximately 1 of 1000 pregnancies—but when it does happen, it can take months of recovery and even become cancerous.
This condition requires months of medical monitoring and can be scary, so it’s important to understand what this complication is and what to expect for the following months. This post will explain:
- What is a molar pregnancy, including what are the risks for developing one?
- Is it the same as a miscarriage?
- What is the difference between partial and complete forms?
- How is this condition treated?
- How does it become cancerous?
What is a molar pregnancy?
A molar pregnancy is when there is a defect in the cells forming the placenta (aka trophoblast cells). Either the cells grow too fast—much faster than than the embryo grows—or around a non-viable embryo. For this reason, this complication is also known as a gestational trophoblastic disease.
How do I know if I have a molar pregnancy?
Initially, the abnormal placenta growth will still secrete the hormone hCG, leading to a positive pregnancy test, seeming like a normal pregnancy even though the embryo isn’t viable. Here are the signs of a molar pregnancy occurring:
- Heavy bleeding early in pregnancy along with high levels of hCG
- High blood pressure early in pregnancy (before 20 weeks)
Your doctor can confirm presence of this abnormality with an ultrasound, revealing no fetus and typically a grape-like cluster of cells.
What are risk factors for molar pregnancy?
Age is a risk factor for this complication, with woman younger than 25 and older than 35 at higher risk. Also, previous history of molar pregnancies increases risk for additional ones.
Is it the same as a miscarriage?
A molar pregnancy is not quite the same as a miscarriage. While causes of miscarriage are usually chromosomal abnormalities, a molar pregnancy happens because of a problem with formation of the placenta. Unfortunately, both scenarios result in pregnancy loss.
How soon after a molar pregnancy can I try conceiving again?
Another key difference between this complication and miscarriage is how soon you can try to conceive again. Getting pregnant after a miscarriage can happen as soon as you’re ready. However, after a molar pregnancy, complications can result in persistent cell growth, so your doctor may ask you to wait 6 – 12 months before trying to conceive.
What is the difference between a partial and complete molar pregnancy?
A complete molar pregnancy means that sperm tried to fertilize an empty egg (aka, an egg with no DNA). But, even though conception didn’t happen, the placental cells kept growing, forming a tissue mass that is completely placental cells (aka, the mole).
A partial molar pregnancy means that fertilization happened, but it resulted in a non-viable embryo (like, two sperm fertilizing one egg). But, even though the embryo cannot survive, the placental cells kept growing, and they grow very quickly, engulfing the embryo. So, the growing tissue mass is partially placental cells and partially fetal cells.
What is a molar pregnancy treatment?
Molar pregnancies can sometimes resolve naturally with expelling of the placental tissue. But, depending on how long the tissue has been growing, a dilation and curettage (D & C) procedure can be necessary to completely remove this tissue.
To ensure that the growths are completely removed, your doctor will likely continue to monitor your hCG levels for several weeks or longer. If the hCG levels do not return to normal, it can indicate that more molar tissue is growing.
How does a molar pregnancy become cancerous?
A potential complication is choriocarcinoma, or when these placenta cells break away from the uterus and travel to other parts of the body to grow. To check for this, your doctor will need to visualize the other growths using a CT scan or x-ray. Chemotherapy can treat these growths. Also, your doctor will recommend waiting 6 – 12 months before trying to conceive again for accurate monitoring of any additional growths.