Overview
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.
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.
The HFEA (Human Fertilisation & Embryology Authority) regulate all fertility clinics in the UK. The following information explains how the figures are calculated.
Information about success rates is of limited value when you're comparing centres and choosing where to have treatment.
The HFEA has information about choosing a fertility clinic.
How the pregnancy results are calculated
A positive pregnancy is confirmed with either a urine (pee) or blood test. We provide you with the urine pregnancy test kit after each embryo transfer.
A clinical pregnancy is confirmed only after the pregnancy sac and fetus have been seen on an ultrasound scan, 2 to 4 weeks after a positive pregnancy test.
We calculate the clinical pregnancy rate per embryo transfer, to indicate how many embryo transfer procedures have resulted in a clinical pregnancy. We also calculate the clinical pregnancy rate per embryo transferred, to indicate the likelihood of a clinical pregnancy per embryo transferred into the womb.
All these results are for people having IVF or ICSI using their own eggs.
Cycles data
This table shows clinical pregnancy rates from 1 January 2022 to 31 December 2023 (2 years).
| Age group | Number of fresh embryo transfer procedures | Clinical pregnancy rate per embryo transfer | Clinical pregnancy rate per embryo transferred |
|---|---|---|---|
| 18 to 34 years | 398 | 40% | 34.3% |
| 35 to 37 years | 413 | 33.4% | 27.4% |
| 38 to 39 years | 329 | 26.7% | 18.4% |
| 40 to 42 years | 248 | 26.2% | 15.5% |
| 43 years or older | 74 | 14.9% | 8.1% |
| Multiple- pregnancy rate | 1,462 | 1.8% |
This table shows pregnancy rates from 1 January 2022 to 31 December 2023 (2 years).
These figures are based on the age of the patient at the time the egg was collected and frozen, and not the age of the patient at the time of the transfer.
| Age group | Number of fresh embryo transfer procedures | Clinical pregnancy rate per embryo transfer | Clinical pregnancy per embryo transferred |
|---|---|---|---|
| 18 to 34 years | 1,465 | 45.3% (664) | 42.3% |
| 35 to 37 years | 723 | 37.8% (273) | 34.3% |
| 38 to 39 years | 327 | 34.9% (114) | 28.8% |
| 40 to 42 years | 175 | 22.9% (40) | 17.4% |
| 43 years or older | 35 | 20% (7) | 13% |
| Multiple- pregnancy rate | 2,725 | 1.2% (33) |
Live birth data
Our aim is for the treatment to result in the live birth of a baby. We ask all our patients to tell us the outcome of their pregnancy, so that we can provide the live birth rate to the HFEA.
The duration of a pregnancy means that the most recent complete live birth data is from 2022.
These figures show live birth rates, for people having IVF or ICSI treatment using their own eggs, from 1 January 2022 to 31 December 2022 (1 year).
This table shows the live birth rate after a fresh embryo transfer.
| Age group | Number of embryo transfer procedures | Live birth rate per embryo transfer | Live birth rate per embryo transferred | |
|---|---|---|---|---|
| 18 to 34 years | 209 | 35% | 28% | |
| 35 to 37 years | 212 | 27.4% | 22% | |
| 38 to 39 years | 165 | 21.2% | 14% | |
| 40 to 42 years | 116 | 12.3% | 7% | |
| 43 years or older | 34 | 6% | 3.2% | |
| Multiple-pregnancy rate | 735 | 1.8% |
The table below shows the live birth rate after a frozen embryo transfer.
These figures are based on the age of the patient at the time it was collected and frozen, and not at the age of the patient at the time of the transfer.
| Age group | Number of frozen embryo transfer procedures | Live birth rate per embryo transfer | Live birth rate per embryo transferred | |
|---|---|---|---|---|
| 18 to 34 years | 692 | 36.4% | 34.1% | |
| 35 to 37 years | 359 | 28.4% | 25.8% | |
| 38 to 39 years | 134 | 27.6% | 22.8% | |
| 40 to 42 years | 80 | 16.3% | 12.6% | |
| 43 years or older | 13 | 30.8% | 21.1% | |
| Multiple-pregnancy rate | 1,278 | 1.2% |
Information and support
You can find more detailed information about IVF 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
