What is a blighted ovum?

A blighted ovum is a type of miscarriage that can happen early in a pregnancy. It is also called an 'anembryonic pregnancy' as there is no embryo (developing baby). In this type of miscarriage, a sac and placenta grow, but there is no baby. Because a blighted ovum still makes pregnancy hormones, it may still show up as a positive pregnancy test.

A blighted ovum will eventually cause a miscarriage, usually at 7 to 12 weeks of pregnancy. Your body realises that the pregnancy is not developing properly and starts to shed blood and tissue from the uterus. You may notice pain in your lower abdomen, or bleeding from your vagina.

How common is miscarriage?

Miscarriage is very common, and up to 1 in 5 people who know that they are pregnant will miscarry before 20 weeks of gestation. The actual rate of miscarriage is even higher, as a very early miscarriage may happen before you even realise that you’re pregnant.

What causes a blighted ovum?

When the egg is fertilised, cells that make the pregnancy sac and placenta start multiplying. But occasionally, the cells that are supposed to develop into a baby don’t multiply.

The cause isn’t known. It isn’t caused by anything you have done.

How and when is blighted ovum diagnosed?

Sometimes, it is picked up during a routine ultrasound. This can be particularly difficult if you’ve gone for an ultrasound expecting good news.

At other times, there may have been bleeding at the start of the pregnancy and an ultrasound is used to investigate the cause.

How is blighted ovum treated?

Your doctor will discuss the options with you. You might choose to allow a natural miscarriage to happen. Once this starts, it can take days or weeks for the bleeding to finish. If the bleeding is getting heavier, if you are in pain or you feel unwell, see your doctor.

You could also have a termination by taking medicines or by having a type of surgery known as D & C.

Does it affect my chances of having a baby?

No. Having a blighted ovum in one pregnancy does not alter your chance of having a successful pregnancy in the future.

If you have had one miscarriage, your next pregnancy is likely to be normal. If you have had 3 miscarriages in a row, you should see your doctor to rule out any problems.

Where can I go for support and information?

Speak with your doctor if you are concerned that you may have a blighted ovum.

A miscarriage can be extremely upsetting. If you’ve experienced a miscarriage you may need support and time to grieve. There is no right way to feel after a miscarriage. Different people react to a miscarriage with different emotions, including anger, guilt or relief.

Pregnancy, Birth and Baby helpline can offer emotional support and trusted advice to anyone who is dealing with pregnancy loss. Call Pregnancy, Birth and Baby on 1800 882 436 anytime of the day or night.