In vitro fertilisation (IVF) is one of several techniques available to help people with fertility problems have a baby.
During IVF, an egg is removed from the woman's ovaries and fertilised with sperm in a laboratory. The fertilised egg, called an embryo, is then returned to the woman's womb to grow and develop.
It can be carried out using your eggs and your partner's sperm, or eggs and/or sperm from donors.
The National Institute for Health and Care Excellence (NICE) has published fertility guidelines that make recommendations about who should have access to IVF treatment on the NHS in England and Wales.
These guidelines recommended that IVF should be offered to women under 43 years of age who have been trying to get pregnant through regular unprotected sex for two years, or who have had 12 cycles of artificial insemination.
However, the final decision about who can have NHS-funded IVF in England is made by local Clinical Commissioning Groups (CCGs), and their criteria may be stricter than those recommended by NICE.
If you're not eligible for NHS treatment, or you decide to pay for IVF, you can have treatment at a private clinic. Costs vary, but one cycle of treatment may cost up to £5,000 or more.
Read more about the availability of IVF.
If you're having trouble getting pregnant, you should start by speaking to your GP. They can advise on how to improve your chances of having a baby.
If these measures don't work, your GP can refer you to a fertility specialist for a treatment such as IVF.
Read more about getting started with IVF.
IVF involves six main stages:
Once the embryo(s) has been transferred into your womb, you'll need to wait two weeks before having a pregnancy test, to see if the treatment has worked.
Read more about what happens during IVF.
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 a successful pregnancy. 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 was:
Maintaining a healthy weight and avoiding alcohol, smoking and caffeine during treatment may improve your chances of having a baby with IVF.
IVF doesn't always result in pregnancy, and it can be both physically and emotionally demanding. You should be offered counselling to help you through the process.
There are also a number of health risks involved, including:
Read about personal experiences of IVF: