IVF treatment

In vitro fertilisation (IVF) helps people with fertility problems to have a baby. It works by:

  • taking an egg
  • fertilising it with sperm in a laboratory
  • putting the fertilised egg (embryo) back inside the womb to grow

IVF is a complex process with several different stages to understand. If you have questions, please speak to a doctor or nurse caring for you.

To find out more about starting IVF, you can contact our assisted conception unit

IVF treatment cycles

A treatment cycle is made up of 5 steps.

Step 1: Medicines to produce eggs 

We give you medicine that temporarily switches off (suppresses) the hormone that releases your eggs. This means that we can control when your eggs are released.

You have another medicine to encourage or 'stimulate' your ovaries to produce more eggs. The aim is to collect as many eggs as possible.

Read more about step 1: Medicines to produce eggs 

Step 2: egg collection

Your eggs are collected from your ovaries.

Read more about step 2: egg collection

Step 3: sperm collection

A sample of semen (the fluid that contains sperm) is produced by your partner. If using frozen or donated (donor) sperm, the sample is prepared.

Read more about step 3: sperm collection

Step 4: fertilisation

We put the eggs and sperm together in a laboratory dish. They can then be fertilised and develop into an embryo (fertilised egg).

Sometimes, each egg needs to be injected individually with a single sperm. This is called intra-cytoplasmic sperm injection or ICSI.

Read more about step 4: fertilisation

Step 5: embryo transfer to the womb

We put the embryos in your womb. This is usually on day 2, 3 or 5 after your egg collection when the fertilised egg has divided. We might freeze your embryos if we cannot transfer them straight away or if there are extra ones.

Read more about step 5: embryo transfer to the womb

Success rates for IVF

It is important to be realistic about the chances of having a successful IVF treatment cycle. The success of IVF depends mainly on your age when you have treatment. Your chances increase as you progress successfully through each step of the treatment process.

Your chances of a clinical pregnancy (when an ultrasound scan confirms a fetal heartbeat) are:

  • 1 in 3, when you start a cycle
  • 1 in 2 if you are under 35 years old and have a blastocyst embryo transfer (this is when we put embryos in your womb that are better developed by day 5 after your egg collection)

Information and support

You can find more detailed, up-to-date information about our success rates on the Human Fertilisation and Embryology Authority (HFEA) website.

You might find it useful to speak to other people in a similar situation through the HealthUnlocked IVF community.

Resource number: 2687/VER4
Last reviewed: July 2023
Next review: July 2026


Trusted Information Creator. Patient Information Forum

Contact us

If you have any questions about IVF, please contact our assisted conception unit (ACU).

Phone: 020 7188 2300

Email: [email protected]

Do you have any comments or concerns about your care?

Contact our Patient Advice and Liaison Service (PALS)

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