What is molar pregnancy?

What is a molar pregnancy?

A molar pregnancy is a type of pregnancy with no growing baby inside the uterus but rapidly growing placenta-like cells instead.

What causes a molar pregnancy?

In a molar pregnancy, the fertilised egg doesn’t contain the right amount of genetic material. A normal fertilised egg contains two sets of genetic material – one from the mother and one from the father.

• In a complete molar pregnancy, a sperm fertilises an empty egg, so the only genetic material inside comes from the father. This forms a mass of abnormal placenta-like cells but no developing baby.
• In a partial molar pregnancy, two sperm fertilise one egg, so there’s too much genetic material inside. The baby starts to develop but doesn’t develop properly.

Who is at risk of having a molar pregnancy?

A molar pregnancy affects only one in 700 pregnancies. All women are at risk, but you’re more prone if you:

1. Are older than 35 and younger than 20
2. Are Asian – you are twice as likely to have a molar pregnancy
3. Have had a previous molar pregnancy – your risk is increased, with repeat molar pregnancy occurring in one out of 100 pregnancies.

What are the symptoms of molar pregnancy?

A molar pregnancy causes the usual pregnancy signs and symptoms, such as a missed period, morning sickness, tender breasts and tiredness.¹ But it can also cause:

• Vaginal bleeding often accompanied by the passing of small grape-like cysts
• Severe morning sickness
• Very high blood pressure
• An unusually big uterus.

Some of the above symptoms can appear in a normal pregnancy as well, so they’re not necessarily a sign that something is wrong. If you’re worried about any symptoms, speak to your midwife or GP.

How is a molar pregnancy diagnosed?

A molar pregnancy often goes undetected until a pregnancy scan is performed. Sometimes vaginal bleeding is the first sign of a molar pregnancy. If you notice any vaginal bleeding in early pregnancy, you will usually be referred for an ultrasound scan to rule out any problems with your baby.

If a molar pregnancy is suspected, you may also have some blood and urine tests to check your levels of human chorionic gonadotropin hormone (hCG) as these are abnormally high in a molar pregnancy.

What are the treatment options?

If you have a molar pregnancy, the abnormal cells are usually removed with a simple suction procedure. You will require ongoing blood test monitoring to check your hormone levels have dropped to make sure that no abnormal cells remain embedded in the womb.

Sex and pregnancy after a molar pregnancy

You can have sex again once the vaginal bleeding has stopped, as long as you feel ready. You will be advised to use contraception as it’s important not to get pregnant again until the hormone levels have returned to normal and you have been discharged.

Most women go on to have a normal pregnancy after a molar pregnancy.