Molar pregnancy

Molar pregnancies are when the baby and the placenta develop in an unusual way, and fluid-filled sacs will grow in clusters inside of the womb.

Usually, when a baby is growing in the womb, the process goes smoothly, and everything happens as it should. However, on rare occasions, something unexpected can happen.

A molar pregnancy is an unusual situation where the baby starts to develop, but can't continue growing as expected.

If this happens, it's important to know you’re not to blame. It's just one of those things that happen by chance.


What are the symptoms of molar pregnancy?

Sometimes, molar pregnancy has no symptoms and may not be noticed until the pregnancy unexpectedly ends. In other cases, mothers have some of the symptoms of a typical pregnancy.

Common signs that could indicate a molar pregnancy include:

  • Severe morning sickness
  • A swollen stomach or unusually large baby bump
  • Vaginal bleeding or dark discharge

Remember that these symptoms can also occur in normal pregnancies. If you have any of these symptoms, you should seek medical attention to get a proper diagnosis.

 In rarer cases, a molar pregnancy may also cause symptoms such as:

  • Tiredness
  • Weakness
  • Twitching or trembling
  • Stomach pain
  • High blood pressure

You should get medical help if you’re worried about these or any other symptoms.


What is a molar pregnancy?

In a molar pregnancy, the baby and the placenta develop in an unusual way, and fluid-filled sacs will grow in clusters inside of the womb. This is also sometimes known as a hydatidiform mole.

There are two types of molar pregnancy.

Complete molar pregnancy

There’s no sign of a baby. None of the cells you’d see in a typical pregnancy grow in the womb.

Partial molar pregnancy

There are some early signs of a baby. However, it won’t be able to develop or survive to full term.


Diagnosing a molar pregnancy

Medical professionals will be able to diagnose a molar pregnancy. If they suspect you have a molar pregnancy, your midwife or doctor will book you in for some tests.

Typically, a blood test will be used to check the mother’s level of a pregnancy hormone called human chorionic gonadotrophin (hCG). All pregnant women produce this hormone to help the baby to develop. However, if you have a molar pregnancy, the levels of these hormones could be higher than in a non-molar pregnancy.

It's normal to be given an appointment with a gynaecologist or an early pregnancy assessment unit. They’ll be able to give you the help and support you need during this difficult time.

Finally, you’ll also be booked in for an ultrasound scan.


Ultrasound of molar pregnancy

It’s normal for pregnant women to have an ultrasound scan of their tummy between 8 to 14 weeks into their pregnancy. This scan can detect a molar pregnancy. However, if your doctor or midwife is worried about your pregnancy before your routine scan, they can also book you in for an internal ultrasound molar pregnancy scan.

During an internal ultrasound (otherwise known as a transvaginal ultrasound), a special ultrasound scanner is placed inside your vagina. This shows a clearer picture of your womb than an external ultrasound scan. It won’t hurt, but it might feel a bit uncomfortable.

If you have a molar pregnancy, the scan results won’t look like a baby and will instead appear like a snowstorm or pattern.

While ultrasound scans are very good at finding complete molar pregnancies, they might not pick up on partial molar pregnancies. This is why it's important to also have a blood test.


Molar pregnancy treatment

As a molar pregnancy isn’t viable, it’s likely that your pregnancy will end naturally.

If not, you’ll need help to end the pregnancy. You may be offered an operation under general anaesthetic. Alternatively, you’ll be given medicine that will end your pregnancy.

You’ll usually be able to go home the same day.

After treatment for molar pregnancy

Afterwards, your hCG hormone levels will be checked using blood and urine tests to see if they have gone down. You’ll also have regular follow-up appointments for at least half a year to check your hCG levels. If your levels don’t go back to normal, you may need further treatment.

After a molar pregnancy, you'll need to use contraception while your hCG levels return to normal. Your GP or medical professional will be able to advise on this.

Remember that you still have every chance of becoming pregnant again and having a healthy baby.

Complications from molar pregnancy

In very rare cases, molar pregnancy can cause a form of cancer to form, known as GTN (gestational trophoblastic neoplasia). This is more common with complete molar pregnancies and usually occurs when some molar tissue remains in the uterus.

GTN may sound serious, but it has a very high cure rate of over 99%, and your doctor will be able to diagnose it when checking your hCG levels. It doesn’t affect your ability to have a baby in the future.

To treat GTN, you might need another operation or chemotherapy. This treatment will continue until 6 weeks after your hCG levels return to normal.

In very rare cases, you may need to have your womb removed to cure GTN.


What causes a molar pregnancy?

The exact causes of molar pregnancy are unknown, but it is known that it happens because of problems with the fertilised egg.

If you or your partner have a molar pregnancy, you’ve not done anything wrong. It’s simply random chance.

This chance increases if:

  • You’re in your early teens
  • You’re over 45 years old
  •  You've had a molar pregnancy before
  • You have an Asian background. This doubles the chance of molar pregnancy
  •  You have low levels of carotene and folic acid. You can help this by eating a balanced diet and taking folic acid tablets for 3 months before pregnancy and for the first 12 weeks. However, do not take supplements that include vitamin A, as it could harm your baby


Dealing with molar pregnancy

Having a molar pregnancy can be hard to deal with, for both your body and your mind.

You don’t have to face this alone. You might find it helpful to talk to your partner, friends and family about the process. Your doctor, nurse or specialist will also be able to recommend or refer you for specialist help if you feel you need it.

Remember: lots of mums who have faced similar challenges have gone on to have healthy pregnancies and babies. 


You can use your cover to pay for treatment for molar pregnancy

You could use your health insurance cover to claim for treatment for a molar pregnancy. The first step is to get a referral from your GP, or through our Digital GP app^. Then you can make a claim through MyAviva, over the phone, or online. You can read more on the terms and conditions of claiming within your policy documents.

If we confirm that your claim meets the terms of your policy, we’ll pay for the treatment directly. Just be sure to tell us if you need more tests or treatment, or if your hospital or specialist changes.

It’s good to have one less thing to worry about. It takes Aviva. 

^ These services are non-contractual and can be withdrawn or amended by Aviva at any time.

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