Before starting IVF, it's important to be aware of the potential problems you could experience.

Many women will have some reaction to the medicines used during IVF. Some of the side effects can be mild.

Side effects can include:

• hot flushes
• feeling down or irritable
• headaches
• restlessness
• ovarian hyperstimulation syndrome

Contact the fertility clinic if you experience persistent or worrying side effects during treatment.

If more than 1 embryo is replaced in the womb as part of IVF treatment, there's an increased chance of producing twins or triplets.

Having more than 1 baby may not seem like a bad thing, but it significantly increases the risk of complications for you and your babies.

Problems more commonly associated with multiple births include:

• miscarriage
• pregnancy-related high blood pressure and pre-eclampsia
• gestational diabetes
• anaemia and heavy bleeding
• needing a caesarean section

Your babies are also more likely to be born prematurely or with a low birth weight, and are at an increased risk of developing life-threatening complications such as newborn respiratory distress syndrome (NRDS) or long-term disabilities, such as cerebral palsy.

National Institute for Health and Care Excellence (NICE) guidelines recommend that double embryo transfers should only be considered in women aged 40 to 42.

Younger women should only be considered for a double embryo transfer if there are no top-quality embryos to choose from.

Read more about the Human Fertilisation and Embryology Authority (HFEA) campaign to reduce multiple births

Ovarian hyperstimulation syndrome (OHSS) is a rare complication of IVF.

It happens in women who are very sensitive to the fertility medicine taken to increase egg production. Too many eggs develop in the ovaries, which become very large and painful.

OHSS generally develops in the week after egg collection.

The symptoms can include:

• pain and bloating low down in your tummy
• feeling and being sick
• shortness of breath
• feeling faint

Severe OHSS can be dangerous. Contact your clinic as soon as possible if you have any of these symptoms. 

It may be necessary to cancel your current treatment cycle and start again with a lower dose of fertility medicine.

If you have IVF, you have a slightly higher risk of having an ectopic pregnancy, where the embryo implants in a fallopian tube rather than in the womb.

This can cause pain in the tummy, followed by vaginal bleeding or dark vaginal discharge.

If you have a positive pregnancy test after IVF, you'll have a scan at 6 weeks to make sure the embryo is growing properly and that your pregnancy is normal.

Tell your doctor if you experience vaginal bleeding or stomach pain after having IVF and a positive pregnancy test.

IVF treatment becomes less successful with age. In addition, the risk of miscarriage and birth defects increases with the age of the woman.

Your doctor will discuss the increased risks that come with age and can answer any questions you may have.