Risks of fertility treatment

How safe is fertility treatment?

Fertility treatment is generally very safe and most who have it experience no problems with their health or pregnancy. However, there are some risks to be aware of, which include:

• having a multiple pregnancy or birth (twins, triplets or more)
• ovarian hyperstimulation syndrome (a severe reaction to fertility drugs)
• having an ectopic pregnancy
• possible birth defects (these are rare and research is still ongoing).

What do I need to know about multiple births?

Multiple births (twin, triplet or more babies) can seriously harm the health of both mum and babies. At least half of twins are born premature and underweight, which can lead to serious (in some cases, long-term) health problems and even death. You’re also far more likely to have an early or late miscarriage if you’re carrying multiple babies.

Mums of multiples are also more likely to suffer from health problems such as high blood pressure, gestational diabetes, anaemia and haemorrhage than mothers of single babies. That’s why we say a single, healthy baby is always best.

What can I do to reduce my chance of having a multiple birth?

Many women have what’s called an elective single embryo transfer (eSET). This means that only one embryo is transferred to your womb instead of two or three as has been common in the past.

This considerably reduces your chance of having a multiple birth and all the health problems that come with that. Any remaining embryos can be frozen for you to use in follow up treatment if you wish.

Find out more about embryo freezing

Having an eSET has no significant impact on success rates. However, it may not be suitable for everyone, particularly older women, so you should talk to your clinic to find out whether it’s right for you.

Find out more about eSET

We’ve set clinics a target that less than 10% of their IVF births should be multiples. You can search for a clinic on our website here to see how they’re doing against that target.

What do I need to know about ovarian hyperstimulation syndrome?

Ovarian hyperstimulation syndrome (OHSS) is reaction to gonadotrophin fertility drugs taken to increase egg production. OHSS occurs in women who are very sensitive to the fertility medication resulting in too many eggs developing in the ovaries, which become very large and painful. Around a third of women will have mild OHSS, which can normally be effectively treated at home with pain relief.

Fewer women will develop moderate or severe OHSS but, in very rare cases, severe OHSS can be life-threatening so it’s very important you report any symptoms to your clinic.

Symptoms of OHSS include:

• swollen stomach and stomach pains (can be severe)
• nausea and vomiting
• shortness of breath
• faintness
• reduced urine output.

Patients who develop strong OHSS symptoms generally do so the week after egg collection.

If you experience any of these symptoms you should contact your clinic immediately. Never feel you are wasting the clinic’s time.

Find out more about OHSS on the Royal College of Obstetricians and Gynaecologists’ website

What do I need to know about ectopic pregnancies?

An ectopic pregnancy is when a baby develops outside of the womb, usually in the fallopian tube. Sadly, when this happens, it’s not possible to move the baby so the pregnancy will be lost.

In these cases it’s important to get medical help as quickly as possible, as ectopic pregnancies that are left for too long can cause rupturing in the fallopian tubes leading to internal bleeding.

All pregnant women are at risk of having an ectopic pregnancy but women having IVF may be more at risk. This is due to the possibility that whilst the embryo is being transferred to the womb it could travel to the fallopian tube instead.

Symptoms of an ectopic pregnancy include:

• a one-sided low abdominal pain
• vaginal bleeding or dark brown or red vaginal discharge
• diarrhoea or pain when you go to the toilet.

If you experience any of these symptoms you should contact your clinic immediately. Never feel you are wasting the clinic’s time.

Find out more about ectopic pregnancies on The Ectopic Pregnancy Trust website

What do I need to know about birth defects?

Some research has suggested that fertility treatment may be associated with an increased chance of birth defects. It’s not yet clear whether the birth defects are a result of the fertility treatment itself or fertility problems in the parents.

The main thing to know is that birth defects in the general population are low. If fertility treatment is associated with an increased chance of birth defects, the risk is still very low.

Research in this area is ongoing and we will continue to review and update our information as more evidence becomes available.

What do I need to know about risks in pregnancy following treatment?

Some research has suggested that patients who undergo a programmed compared to a natural cycle frozen embryo transfer may be at an increased risk of experiencing high blood pressure during pregnancy.

Research in this area is ongoing and we will continue to review and update our information as more evidence becomes available. If you have any concerns, we encourage you to discuss these with a clinician at your fertility clinic or another medical professional such as your GP.

High blood pressure in pregnancy can be serious. You can find out more about high blood pressure (hypertension) and pregnancy on the NHS website.