IVF - What is in vitro fertilisation (IVF) and how does it work?
What is IVF?
IVF treatment involves the fertilisation of an egg (or eggs) outside the body. The treatment can be performed using your own eggs and sperm, or using either donated sperm or donated eggs, or both.
Is IVF for me?
Your clinic may recommend IVF if:
- you have been diagnosed with unexplained infertility
- your fallopian tubes are blocked
- other techniques such as fertility drugs or intrauterine insemination (IUI) have not been successful
- the male partner has fertility problems but not severe enough to require intra-cytoplasmic sperm injection (ICSI)
- you are using your partner’s frozen sperm in your treatment and IUI is not suitable for you
- you are using donated eggs or your own frozen eggs in your treatment
- you are using embryo testing to avoid passing on a genetic condition to your child (see p61).
How does IVF work?
IVF techniques vary according to your individual circumstances and the approach of your clinic. Before your treatment starts, you will need to complete various consent forms (see p81). You and, if applicable, your partner may also need to have blood tests to screen for HIV, hepatitis B, hepatitis C and human T cell lymphotropic virus (HTLV) I and II..
Treatment then typically involves the following stages:
1. Suppressing your natural monthly hormone cycle
As a first step you will be given a drug to suppress your natural cycle, which you can administer yourself in the form of a daily
injection or a nasal spray. The drug treatment continues for about two weeks.
2. Boosting the egg supply
After your natural cycle has been suppressed, you will be given a type of fertility hormone known as a gonadotrophin. You will usually take this as a daily injection for around 12 days. The hormone will increase the number of eggs you produce.
3. Checking on progress
The clinic will monitor your progress throughout the drug treatment through vaginal ultrasound scans and, possibly, blood tests. Between 34 and 38 hours before your eggs are due to be collected you will be given a hormone injection to help your eggs mature. This is likely to be human chorionic gonadotrophin (hCG).
4. Collecting the eggs
Your eggs will usually be collected using ultrasound guidance while you are sedated. A hollow needle is attached to the ultrasound probe and is used to collect the eggs from the follicles on each ovary. You may experience some cramps, feel a little sore and bruised and/or experience a small amount of bleeding from the vagina. After your eggs have been collected, you will be given medication in the form of pessaries, injection or gel to help prepare the lining of your womb for embryo transfer.
Step 5. Fertilising the eggs
Your eggs will be mixed with your partner’s or the donor’s sperm and cultured in the laboratory for 16–20 hours after which they are checked for signs of fertilisation.
Those that have been fertilised (now called embryos) will be grown in the laboratory incubator for up to six days. The embryologist will monitor the development of the embryos and the best will then be chosen for transfer. Any remaining embryos of suitable quality can be frozen for future use.
Step 6. Embryo transfer
If you are under the age of 40, one or two embryos may be transferred. If you are 40 or over, a maximum of three may be used.
The number of embryos transferred is restricted because of the risks associated with multiple births. Due to this, your clinic will recommend single embryo transfer (SET) if they feel it is the best option for you.
During the procedure, a doctor or nurse will insert a speculum into your vagina. This is similar to having a cervical smear taken, when a speculum is used to hold the vagina open so the cervix is visible.
A fine tube (catheter) is then passed through the cervix, normally using ultrasound guidance. The embryos are passed down the tube into the womb.
This is normally a pain-free procedure and usually no sedation is necessary, but you may experience a little discomfort because you need a full bladder if ultrasound is used.
Around the time your partner’s eggs are collected, you will be asked to produce a sample of sperm.
The sperm will be washed and prepared so the active, normal sperm are separated from the poorer-quality sperm.
If you have stored sperm, it will be removed from frozen storage, thawed and prepared in the same way.
Page last updated: 11 August 2014