A molar pregnancy is a complication that happens very early on in pregnancy.
Sadly, it results in an abnormality in the growth of placenta tissue when the egg implants itself in the uterus.
And in almost all cases, it means that the developing baby cannot be carried to term.
It can be incredibly traumatic to undergo a pregnancy complication of any sort, and, whether you’re trying to get pregnant or not, can leave you feeling emotionally and physically spent.
Remember, it’s OK to feel however it is that you feel.
So if you’re after more information and answers to your pressing questions, we’re exploring everything there is to know about having a molar pregnancy.
Content warning: In this article, we’ll discuss details of pregnancy loss which can be hard to read. We hope this provides the information you’re looking for, and that you have the support you need.
In this article: 📝
- What is a molar pregnancy?
- Complete vs partial molar pregnancy
- Is there a baby in a molar pregnancy?
- Symptoms of molar pregnancy
- How soon can you detect a molar pregnancy?
- What causes a molar pregnancy?
- More on molar pregnancies
What is a molar pregnancy?
Known medically as hydatidiform mole, a molar pregnancy results from abnormal fertilization of an egg.
Sadly, in cases of a molar pregnancy, the fetus won’t survive.
There’s also a chance that a molar pregnancy can cause health issues with the mother, too, so the sooner you find a molar pregnancy, the better.
How common is a molar pregnancy?
About 1 in 1,000 pregnancies in the US is a molar pregnancy.
But most women who have a molar pregnancy go on to have a healthy pregnancy at a later date.
Types of molar pregnancy
There’s two types of molar pregnancy: complete molar pregnancy and partial molar pregnancy.
The key difference between the two is that in complete molar pregnancy, the anomaly occurs at fertilization, whereas with a partial molar pregnancy, the anomaly occurs with the growth of the placenta.
To better understand this, let’s go back a little to the process of fertilization and what can result if things take a detour.
When an egg is fertilized, it goes on a trip from the fallopian tubes to find itself a home in the lining of the uterus.
This last part is called implantation.
At implantation, the placenta begins to develop so that it can carry out its job of providing nutrients and oxygen.
It also moonlights as a waste management system. It’s quite impressive!
When it comes to a molar pregnancy, however, things don’t quite go this way.
Complete vs partial molar pregnancy
Let’s dive deeper into the differences between a complete molar pregnancy and a partial:
Complete molar pregnancy
A complete molar pregnancy is all placental tissue with no sign of a fetus.
With a complete molar pregnancy, the egg that is fertilized has an abnormal chromosomal makeup (an empty egg) and can’t develop into a fetus.
Basically, the placental tissue grows but is abnormal and contains fluid-filled cysts.
Partial molar pregnancy
In a partial molar pregnancy, both placental and fetal tissue can be detected.
Essentially, with a partial molar pregnancy, a fetus does develop, but the placenta develops abnormally.
You may have a partial molar pregnancy ultrasound, which will detect the partial molar pregnancy, showing fluid-filled cysts in the uterus.
You may be wondering if it’s possible to have a partial molar pregnancy with a heartbeat ‒ generally speaking, no, a partial molar pregnancy fetus doesn’t have a heartbeat.
In fact, one of the signs of a partial molar pregnancy is the absence of a heartbeat during the partial molar pregnancy ultrasound.
Is there a baby in a molar pregnancy?
Technically speaking, no, a molar pregnancy doesn’t become a baby.
However, a partial molar pregnancy will have a partially-developed fetus, but no heartbeat.
In these cases, the growing embryo has an extra set of chromosomes which means that at an ultrasound, it may look like a fetus, but, sadly, will not be able to develop into a baby.
Ultimately, it’s up to you and your personal definition of a baby.
Can a baby survive a molar pregnancy?
Unfortunately, it’s very unlikely for a fetus to survive a molar pregnancy.
Usually, by the time a molar pregnancy is detected by ultrasound, even a partial molar pregnancy with a fetus, by that time, it hasn’t survived.
However, there are very rare cases in which a molar pregnancy baby survives, such as the baby delivered at 32 weeks in this 1999 study, who, 18 months later, looked to have no further medical complications.
So it is possible to have a molar pregnancy with viable fetus, but it is extremely rare, and can cause preterm delivery and potential harm to both baby and mom.
Will a molar pregnancy test positive?
Yes, more often than not, a molar pregnancy, even after pregnancy loss, will test positive for weeks afterward.
It’s because the placental tissue formed produces the pregnancy hormone hCG.
This increase in hCG levels can go on to give you a positive pregnancy test.
However, there is a study in 2014 that found that molar pregnancies can sometimes test as a false negative pregnancy test, due to a medical phenomenon known as the ‘high dose hook effect’, where very high levels of hCG can cause a false-negative pregnancy test.
Symptoms of molar pregnancy
So what does a molar pregnancy feel like? Is there anything you should be looking out for?
Molar pregnancy symptoms can be hard to detect.
You may just feel as though you are in the early stage of pregnancy.
Having said that, certain warning signs are useful to look out for:
- Vaginal bleeding. Molar pregnancy bleeding is a tricky one during early pregnancy because it can stem from different sources. In the early phase of pregnancy, you might experience implantation bleeding, which is pinkish-brown in color. If your blood is darker red or brown and you see what looks like tissue or clots (particularly clots that look like a collection of ‘bubbles’), reach out to your healthcare provider.
- Intense nausea and vomiting. Again, a tricky one because nausea can be a typical symptom of early pregnancy. Still, if you’re thinking it’s more intense than it should be, it’s not a bad idea to check in with your doc.
- Pain in the pelvic area. If you’re feeling any sort of intense pain in your abdomen, give your healthcare provider a call. And know that it’s okay to be overly cautious.
- Molar pregnancy discharge. Some people with molar pregnancies have reported seeing a watery, brown-colored discharge along with molar pregnancy bleeding.
When do molar pregnancy symptoms start?
But you may experience molar pregnancy symptoms a little earlier.
If you’re ever concerned about any part of your pregnancy, speak with your healthcare provider.
Are molar pregnancies painful?
Sometimes, yes, having a molar pregnancy can cause pelvic and abdominal pain.
You may also notice your pregnancy bump growing faster than expected, due to the abnormal growth of the placental cells.
Do hCG levels rise with molar pregnancy?
Yes, molar pregnancy hCG levels are typically higher than in other pregnancies.
Whether it’s a complete or partial molar pregnancy, hCG levels are likely to continue to be higher for a few weeks after the pregnancy loss.
If you’re after a molar pregnancy hCG levels chart, it’s hard to define the potential hCG levels in figures, because each molar pregnancy is different.
How long does it take for hCG levels to go down after molar pregnancy?
Generally speaking, the higher levels of hCG will return to pre-pregnancy levels about 4-6 weeks after a molar pregnancy has been removed.
In approx 10% of women who have a complete molar pregnancy and 1% of partial molar women, extra treatment is needed to lower hCG levels.
Can you have a molar pregnancy with low hCG?
No. Molar pregnancies tend to show higher levels of hCG than a non-molar pregnancy.
However, due to a scientific phenomenon known as the ‘high dose hook effect’, hCG levels may show as very low in some testing, due to the very high levels during a molar pregnancy.
How soon can you detect a molar pregnancy?
In most cases, you’ll know if it’s a molar pregnancy in the first trimester as it’ll show up in a routine molar pregnancy ultrasound.
Again, however, if you suspect that complications have arisen, check in with your doctor, who can then arrange for an ultrasound for molar pregnancy.
As with all health issues, the sooner you know, the better.
Can you see a molar pregnancy at 6 weeks?
It’s usually during the first ultrasound that a molar pregnancy is detected.
What does a molar pregnancy look like on ultrasound?
A molar pregnancy on ultrasound could look different depending on whether it’s a complete or partial molar pregnancy.
A complete molar pregnancy will show no fetus or amniotic fluid, but instead an overgrown placenta taking up the space of the uterus.
A partial molar pregnancy will show cysts in the uterus; then the doctor will do a test to check hCG levels, which will show as unusually high for this stage in pregnancy.
What causes a molar pregnancy?
Essentially, a molar pregnancy results from chromosomal abnormalities that stop the process early on.
This can be the result of an egg with no genetic info being fertilized, or an egg being fertilized by multiple sperm.
The result is that instead of a baby and placenta forming, fluid-filled cysts form in its place.
The most important thing to remember is that you didn’t do anything wrong.
There is nothing you could’ve done to change this.
Who is at risk for molar pregnancy?
While there’s nothing that you can do to change whether you have a molar pregnancy, there are some risk factors to be aware of.
Risk factors for a molar pregnancy include:
- Your age: Being younger than 15 and older than 43 puts you in a higher risk category for a molar pregnancy.
- Previous molar pregnancy or pregnancy loss: If you’re already had a molar pregnancy, the likelihood of it happening again is higher—but don’t let this deter you. It’s also completely possible to have a pregnancy without complications.
- Where you’re from: Stats show that there are higher rates of molar pregnancy in different parts of the world. That being said, a molar pregnancy can happen to anyone and it is never your fault.
More on molar pregnancies
Whether you’ve been diagnosed with a molar pregnancy, you think you may have one, or you’re researching them just in case, it’s only natural to have some questions.
Let’s see if we can answer them for you.
Can you die from a molar pregnancy?
These days, it’s extremely unlikely that you will die from a molar pregnancy.
Your doctor will remove the tissue in a procedure called a D&C (dilatation and curettage) and most women heal quickly.
In some rare cases, further complications can arise from a molar pregnancy, with persistent tissue continuing to grow after the first lot of tissue has been removed ‒ but this is unlikely.
Your doc will monitor you for a few months after you’ve had your procedure, to make sure that you don’t experience any further issues.
How do they remove a molar pregnancy?
The standard molar pregnancy treatment is to remove the molar tissue, unless you’ve already passed it from miscarriage.
If the molar tissue does continue to abnormal grow, another form of molar pregnancy treatment can be low-risk chemotherapy for molar pregnancy to stop the growth of the abnormal cells.
Does molar pregnancy cause infertility?
No, most molar pregnancies will not cause infertility, although having one molar pregnancy will increase your chances of having another ‒ but many mamas have molar pregnancies and go on to have healthy babies later.
In fact, you can usually start TTC (trying to conceive) once you’ve had your first period after molar pregnancy.
What happens if you get pregnant after molar pregnancy?
Generally speaking, having a molar pregnancy won’t affect future pregnancies.
Although your chances of having another molar pregnancy are increased, the chances are still relatively small.
You may have a few more check-ups with your doctor, but other than that, it’s not likely that your molar pregnancy will affect your future pregnancy.
Can molar pregnancy be misdiagnosed?
You may have heard stories where a molar pregnancy baby survives ‒ while this can happen, as in this study, they are very rare.
However, sometimes, a molar pregnancy can be misdiagnosed.
Generally speaking, it’s easier to misdiagnose a twin pregnancy with a molar pregnancy ‒ due, in part, to the second fetus possibly resembling molar tissue, and the increased hCG levels from both (or multiple) babies.
Beyond these physical effects and symptoms, experiencing a molar pregnancy can be a source of stress, anxiety, and depression.
If you’re currently living through this reality, know that all your feelings are valid.
Remember to reach out for support on Peanut if you need it ‒ there are thousands of women who share your story.