12 min read

What is IVF?

In vitro fertilisation (IVF) is one of several techniques available to help couples with fertility problems to have a baby.

During IVF, an egg is surgically removed from the woman's ovaries and fertilised with sperm in a laboratory. The fertilised egg, now called an embryo, is then returned to the woman's womb to grow and develop.

Read more information about

how IVF is performed

IVF doesn't always result in pregnancy and it can be both physically and emotionally demanding. If you're going through IVF, you should be offered

to help you through the process.

Read more about

support available during IVF

Who can have IVF?

Women under 40

Women aged under 40 who have not been able to get pregnant after 12 cycles of

artificial insemination

However, if tests show IVF is the only treatment likely to help you get pregnant, you should be referred for IVF straight away.

Women aged 40 to 42

40 and 42 may consider IVF if :

  • you have never had IVF treatment before
  • you show no evidence of low ovarian reserve (this is when eggs in the ovary are low in number or low in quality)
  • you have been informed of the additional implications of IVF and pregnancy at this age

Again, if tests show IVF is the only treatment likely to help you get pregnant, you should be referred for IVF straight away.

Read information about

getting started with IVF

Success rate

The success rate of IVF depends on the age of the woman undergoing treatment as well as the cause of the infertility (if it's known). Younger women are more likely to have healthier eggs, which increases the chances of success.

IVF isn't usually recommended for women above the age of 42 because the chances of a successful pregnancy are thought to be too low.

In 2010, the percentage of IVF treatments that resulted in a live birth (the success rate) was:

  • 32.2% for women under 35
  • 27.7% for women aged 35-37
  • 20.8% for women aged 38-39
  • 13.6% for women aged 40-42
  • 5% for women aged 43-44
  • 1.9% for women aged over 44

Read more information about the

risks of IVF

Funding and payment

If you're not eligible for funding or you decide to pay for IVF, you can approach a private fertility clinic directly. Some clinics ask for a referral by your doctor. Costs varies from clinic to clinic and there may be additional costs for medicines, consultations and tests.

Some clinics may offer a ‘package’ of treatment. During your discussions with the clinic, make sure you find out exactly what's included in the price. You may also be able to reduce the cost of IVF by donating some of your eggs or male partner's sperm for others to use.

If you're thinking about having IVF abroad, there are a number of issues you need to consider, including your safety and the standards of care you'll receive. Clinics in other countries may or may not be regulated to local standards and regulations.

Risks of IVF

The potential problems associated with IVF are outlined below.

Drug side effects

Most women will have some reaction to the drugs. Most of the time the side effects are mild and may include:

  • hot flushes
  • feeling down or irritable
  • headaches
  • restlessness
  • nausea and vomiting
  • shortness of breath
  • abdominal bloating
  • ovarian hyperstimulation syndrome (see below) - it may be necessary to cancel the cycle and restart with a lower dose of gonadotrophin

If you have these symptoms, see your doctor immediately, especially if you have abdominal pain and swelling.

Multiple births

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

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

  • you have a higher risk of [miscarriage],
    and heavy bleeding, and are more likely to go into early labour and need a [caesarean section] or assisted [ventouse or forceps delivery]
  • up to 25% of multiple pregnancies cause [pregnancy-related high blood pressure]
  • you're two to three times more likely to develop
    gestational diabetes
    during pregnancy if you're carrying more than one baby
  • the risk of [pre-eclampsia] is three times higher for twin pregnancies and nine times higher for triplets

Ovarian hyperstimulation syndrome

The ovarian hyperstimulation syndrome (OHSS) is a rare complication of IVF. It occurs in women who are very sensitive to the fertility drugs taken to increase egg production. Too many eggs develop in the ovaries, which become very large and painful.

OHSS is more common in women under 30 and in women who have

polycystic ovary syndrome
. OHSS generally develops in the week after egg collection.

The symptoms of OHSS are pain and bloating low down in your abdomen, and nausea or vomiting. Severe cases can be dangerous. Contact your clinic if you have any of these symptoms.

Ectopic pregnancy

If you have IVF, you have a slightly higher risk of an

ectopic pregnancy
, where the embryo implants in the fallopian tubes rather than in the womb. This can cause pain in the abdomen, associated with vaginal bleeding or bleeding into your abdomen.

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

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

How is IVF performed?

The IVF technique was developed in the 1970s. It may differ slightly from clinic to clinic but a typical treatment is as follows.

For women

Step one: suppressing the natural monthly cycle

You are given a drug that will suppress your natural menstrual cycle. This is given either as a daily injection (which you'll be taught to give yourself) or as a nasal spray. You continue this for about two weeks.

Step two: boosting the egg supply

Once your natural cycle is suppressed, you take a fertility hormone called FSH (follicle stimulating hormone). These fertility hormones are known as gonadotrophins. This is another daily injection you give yourself, usually for about 10-12 days, but it can vary depending on your response.

FSH increases the number of eggs your ovaries produce. This means more eggs can be collected and fertilised. With more fertilised eggs, the clinic has a greater choice of embryos to use in your treatment.

Step three: checking on progress

The clinic will keep an eye on you throughout the drug treatment. You will have vaginal ultrasound scans to monitor your ovaries and, in some cases, blood tests. About 34-38 hours before your eggs are due to be collected, you'll have a final hormone injection that helps your eggs to mature.

Step four: collecting the eggs

For the egg collection, you'll be sedated and your eggs will be collected under ultrasound guidance. This involves a needle being inserted through the vagina and into each ovary. The eggs are then collected through the needle.

Some women experience cramps or a small amount of vaginal bleeding after the procedure.

Step five: fertilising the eggs

The collected eggs are mixed with your partner's or the donor's sperm in the laboratory. After 16-20 hours they're checked to see if any have been fertilised.

If the sperm are few or weak, each egg may need to be injected individually with a single sperm. This is called intra-cytoplasmic sperm injection or ICSI (see below).

The fertilised eggs (embryos), continue to grow in the laboratory for one to five days before being transferred into the womb. The best one or two embryos will be chosen for transfer.

After egg collection, you will be given medicines, either progesterone or hCG (chorionic gonadotrophin), to help prepare the lining of the womb to receive the embryo. This is given either as a pessary (which is placed inside the vagina), an injection or a gel.

Step six: embryo transfer

The number of embryos to be replaced should have been discussed before treatment starts.

Women under 37 in their first IVF cycle should only have a single embryo transfer. In their second IVF cycle they should have a single embryo transfer if one or more top-quality embryos are available. Doctors should only consider using two embryos if no top-quality embryos are available. In the third IVF cycle, no more than two embryos should be transferred.

Women aged 37–39 years in the first and second full IVF cycles should also have single embryo transfer if there are one or more top-quality embryos, and double embryo transfer should only be considered if there are no top-quality embryos. In the third cycle, no more than two embryos should be transferred.

For women aged 40-42 years, double embryo transfer can be considered.

All multiple embryo replacements carry the risk of a multiple pregnancy and birth. Multiple pregnancies are associated with a significantly increased risk of premature labour, resulting in a three- to five-fold increased risk of blindness, deafness and cerebral palsy.

Read more about the

risks associated with multiple births

If any embryos are left over, and they're suitable, they may be frozen for future IVF attempts.

The embryo transfer is done either two to three days after egg collection (cleavage stage of embryo development) or five to six days after egg collection (blastocyst stage).

For men

Around the time your partner's eggs are collected, you'll be asked to produce a fresh sample of sperm. The sperm are washed and spun at a high speed, so the healthiest and most active sperm can be selected.

If you're using donated sperm, it is removed from frozen storage, thawed and prepared in the same way.

Recovery after IVF

Undergoing IVF can be emotionally and physically draining. It's important couples are offered counselling when they need it.

Some couples may also find it useful to join a fertility support group or online forum for support, as well as speaking to health professionals.


Counselling may be used to help couples understand the implications of treatment, or for support at a critical time, e.g. when an IVF cycle has been unsuccessful.

Unsuccessful IVF treatment

In many instances, IVF treatment is unsuccessful. Under these circumstances it's a good idea to have a break from treatment and give your body time to recover. A break of two months is often recommended.

This time can give you a chance to talk with the clinic about the reasons the IVF was unsuccessful, to talk to your partner about how you both feel and consider your options going forward.

It can help to talk to other people who have been through IVF. A support group or online forum may be helpful.

Adapting to parenthood

Some couples who have successfully started a family with IVF can find it difficult to adjust to their new life. It's important to seek help from health professionals (e.g. your fertility consultant, doctor, midwife or health visitor).

Contacting a fertility support group and talking with others who can empathise with your experiences can also be helpful.

Why is it necessary

If you're having problems getting pregnant, see your doctor. They will look at your medical history and give you a physical examination.

They may also recommend some

lifestyle changes to help fertility

Unless there are reasons that may put you at high risk of infertility, such as treatment for cancer in the past, you'll only be considered for infertility investigations and treatment after you've been trying for a baby for at least a year without becoming pregnant.

Referral to an infertility specialist

The specialist will ask about your fertility history, and may carry out a physical examination.

For women, you may have tests to check the levels of hormones in the blood and how well the ovaries are working. You may also have an

, to see if there are any blockages or structural problems.

Men may be asked for a semen sample to test sperm quality.

If the specialist thinks your infertility could be treated by IVF, or if you've been unable to conceive for at least two years, you may qualify for funding for IVF treatment.

If IVF is the best treatment for you, the specialist will refer you to an assisted conception unit (see below).

Read more information about

diagnosing infertility

The assisted conception unit

Once you're accepted for treatment at the assisted conception unit, you and your partner will have a blood test for

hepatitis B
hepatitis C
, and to check that you're immune to
(German measles). Also, your
cervical screening tests
should be up to date.

The specialist will investigate the amount of eggs in your body and their quality (your ovarian reserve). It will be assessed by measuring your anti-mullerian hormone (AMH) level.

This can be done with a blood test or by counting the number of egg containing follicles, known as your antral follicle count (AFC), using vaginal ultrasound. An AMH test can be done on any day of your cycle. Your AMH and AFC levels help to estimate how your ovaries will respond to IVF treatment.

Additional semen samples may be required.

The specialist will then discuss your treatment plan with you in detail.

Read more information about

how IVF is performed

You will need to sign consent forms giving permission for the use or storage of your eggs, sperm or embryos throughout the procedure.

You may find you need support and guidance while going through this process. Some people find counselling helpful.

Important: Our website provides useful information but is not a substitute for medical advice. You should always seek the advice of your doctor when making decisions about your health.