IVF is a fertility treatment where an egg is fertilised with sperm outside the body
The resulting embryo is then transferred into the womb
It was originally developed for blocked or damaged fallopian tubes, but now treats many causes of infertility
A full treatment cycle usually takes a few weeks
Success rates depend mainly on age, particularly the age of the person providing the eggs
About IVF
In vitro fertilisation, or IVF, is a fertility treatment where an egg is fertilised with sperm in a laboratory, outside the body, rather than inside the womb. If fertilisation is successful, the resulting embryo is transferred into the womb, with the aim of it implanting and developing into a pregnancy.
IVF was originally developed to help people with blocked or damaged fallopian tubes, but is now used more widely to treat a range of causes of infertility, including endometriosis, ovulation problems, male factor infertility, or where no clear cause can be identified. A single treatment cycle typically takes a few weeks from start to finish.
Page last reviewed: 6 March 2024 · Next review due: 6 March 2027
IVF · Process
How IVF Works
? 5 min readReviewed: March 2024
The Treatment Cycle
A typical IVF cycle involves several stages. First, medicine is used to temporarily suppress your natural hormone cycle, giving the clinical team control over the timing of egg release. Next, daily hormone injections stimulate the ovaries to produce more eggs than usual, with progress tracked through regular ultrasound scans.
Once the eggs are ready, a minor procedure is used to collect them directly from the ovaries. On the same day, a sperm sample is provided (or a previously frozen sample used), which is then prepared in the laboratory to select the healthiest sperm. The eggs and sperm are combined and left to fertilise.
A few days after fertilisation, one or two of the best quality embryos are transferred into the womb, usually on day two, three, or five after egg collection. Any remaining good-quality embryos may be frozen for possible future use.
Page last reviewed: 6 March 2024 · Next review due: 6 March 2027
IVF · Success Rates
Understanding Success Rates
? 4 min readReviewed: March 2024
What Affects Success
The chances of IVF succeeding depend on several factors, but age — particularly the age of the person providing the eggs — tends to have the biggest impact. Success rates are generally highest for those under 35, and gradually decline with age, especially after 40.
It's worth being realistic about the chances of success with any single cycle, and your fertility team can help explain what the figures mean for your particular circumstances, since comparing headline success rates between clinics isn't always a reliable way to choose where to have treatment. All UK fertility clinics are regulated by the Human Fertilisation and Embryology Authority (HFEA), which collects and publishes data on treatment outcomes across the country.
Page last reviewed: 6 March 2024 · Next review due: 6 March 2027
