What happens during IVF may differ slightly from clinic to clinic, but a typical treatment follows the main steps below.
Step one: suppressing the natural menstrual cycle
You are given a medication that will suppress your natural menstrual cycle. This can make the medicines used in the next stage of treatment more effective.
This medication 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 follicle stimulating hormone (FSH). This is another daily injection you give yourself, usually for about 10-12 days.
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 progress
The clinic will keep an eye on you throughout the 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
You'll be sedated and your eggs will be collected using a needle that's passed through the vagina and into each ovary under ultrasound guidance. This is a minor procedure that takes about 15 to 20 minutes.
Some women experience cramps or a small amount of vaginal bleeding after this procedure.
Step five: fertilising the eggs
The collected eggs are mixed with your partner's or the donor's sperm in a laboratory. After 16-20 hours, they're checked to see if any have been fertilised.
In some cases, each egg may need to be injected individually with a single sperm. This is called intra-cytoplasmic sperm injection or ICSI. You can read more about ICSI on the Human Fertilisation and Embryology Authority (HFEA) website.
The fertilised eggs (embryos) continue to grow in the laboratory for up to six 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 hormone medicines to help prepare the lining of the womb to receive the embryo. This is usually given either as a pessary (which is placed inside the vagina), an injection, or a gel.
Step six: embryo transfer
A few days after the eggs are collected, the embryos are transferred into the womb.
This is done using a thin tube called a catheter that's passed into the vagina. This procedure is simpler than egg collection and similar to having a cervical screening test, so you won't normally need to be sedated.
The number of embryos that will be transferred should be discussed before treatment starts. It usually depends on your age.
- 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.
- Women aged 40-42 years may have a double embryo transfer.
If any suitable embryos are left over, they may be frozen for future IVF attempts.
You can read the HFEA factsheets on embryo transfer and freezing and storing embryos for more information.
Around the time your partner's eggs are collected, you'll be asked to produce a fresh sperm sample. 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's thawed before being prepared in the same way.
Finding out if you're pregnant
Once the embryos have been transferred into the womb, you'll be advised to wait around two weeks before having a pregnancy test, to see if the treatment has worked.
Some clinics may suggest carrying out a normal urine pregnancy test at home and letting them know the result, while others may want you to come into the clinic for a more accurate blood test.
This "two-week wait" can be a very difficult period, because of the anxiety of not knowing whether the treatment has worked. Some people find it the hardest part of the treatment process.
During this period, you may find it useful to speak to a counsellor through the fertility clinic, or to contact other people in a similar situation to you via the HealthUnlocked IVF community.
If you do become pregnant, ultrasound scans will be carried out during the following weeks to check things are progressing as expected. You will then be offered the normal antenatal care given to all pregnant women.
Unfortunately, IVF is unsuccessful in many cases and you should try to prepare yourself for this possibility. You may be able to try again if treatment doesn't work, although you shouldn't rush straight into it. You may find counselling or fertility support groups helpful during this difficult time.
Read more about the support available during IVF.