In-vitro fertilisation (IVF)

What are the risks involved with IVF?

IVF does not always lead to a pregnancy.  Success rates can vary depending on a number of factors which your Consultant will discuss with you. It can also be physically and emotionally demanding. Counselling will always be offered to patients to help them through the process.

Additional risks include:

• Multiple pregnancies – There is an increased chance of having multiple pregnancy (i.e. twins or triplets) with IVF if more than one embryo is replaced. Multiple pregnancy can put a significant mental and physical strain on the mother and increase the chance of pregnancy complications.
• Ovarian hyperstimulation syndrome – Ovarian hyperstimulation syndrome (OHSS) is a medical condition affecting the ovaries of some women who take fertility medication to stimulate egg growth. Most cases are mild, but rarely the condition is severe and can lead to serious illness. Your centre will be monitoring the growth of the eggs to identify if you may be at risk.
• Ectopic pregnancy – There is a slight increase risk of having an ectopic pregnancy while undergoing IVF treatment. An ectopic pregnancy occurs when the embryo grows in the fallopian tubes instead of the womb.
• IVF drug side effects – The drugs prescribed as part of IVF treatment may have some side effects. These can differ for each patient but common symptoms include – hot flushes, nausea, migraines, and shortness of breath.

How does IVF work step by step?

These are the main seven stages of IVF:

1. Down regulation
Before beginning fertility treatment drugs are given to suppress the natural hormones produced in a normal menstrual cycle. This results in the ovaries responding more effectively to fertility drugs.

2. Stimulation of the ovaries
Fertility drugs are given in an IVF cycle in order to stimulate the ovaries to produce follicles which contain eggs. The drug is given as a daily injection and will be taken for around 12 days.  
Possible complications: Sometimes the ovaries do not respond very well to the drugs and the treatment cycle may be cancelled.
Ovarian hyperstimulation syndrome (OHSS) may occur if the ovaries over stimulate and produce large numbers of eggs or high levels of oestrogen, but this is rare. Symptoms include abdominal discomfort, but this should settle with rest and mild painkillers.

3. Monitoring egg development
The growth of the follicles is monitored by vaginal ultrasound scans regularly from approximately the sixth day of injections. When the follicles are at the optimum size, a different hormone injection is given to induce the final stages of egg maturation. This injection is given 34 to 36 hours before the eggs are collected.

4. Ultrasound guided egg collection
The most common technique is by using an ultrasound-guided needle, carried out under a light general anaesthetic or intravenous sedation. The procedure, which takes about 30 minutes, is carried out using vaginal ultrasound. Remember, you will not be able to drive after this procedure. A needle is guided along the probe through the vaginal wall and into the ovary. Each follicle in turn is punctured and the fluid it contains is drained and passed to the embryologist to examine to see if an egg is present. Any eggs collected are placed into culture media within culture dishes which are then placed into an incubator in the laboratory.

On average eggs are retrieved from about 80 per cent of mature follicles although on some very rare occasions there may be no eggs collected.

5. Sperm collection
Your partner will be asked to produce a sample of sperm either before or after the egg collection depending on the time of the procedure. He will also be asked to abstain from intercourse for  72 hours before the egg collection. If donor sperm is being used, the sample will be taken from frozen storage. When donor sperm is used in any assisted conception technique recommendations from the Human Fertilisation and Embryology Authority (HFEA) and the British Fertility Society are followed.

6. Fertilisation
After egg collection, eggs are incubated in a special culture medium. At the time of insemination, prepared sperm will be added to the eggs and about 16-20 hours later the first signs of fertilisation become visible under the microscope. The fertilised eggs then remain in culture until the second/ third day, or fifth day after egg collection when they will have become embryos and will be ready for transfer back into the uterus.

7. Embryo transfer
Embryos are transferred through the cervix into the uterus using a catheter. The number of embryos transferred will be discussed with you and will depend on your age, the quality of your embryos, and whether or not you have had any previous treatments. Usually one or two embryos will be transferred.

For more information or if you have any queries, speak to your consultant.