What is it?
In vitro fertilisation (IVF) simply means the fertilisation of an egg by sperm outside the body. The first IVF baby (Louise Brown) was born in Oldham (England) in 1978 following the pioneering work of a gynaecologist (Patrick Steptoe) and a scientist (Robert Edwards).
The techniques have been refined over the last two decades making it possible for many couples to achieve their dream of having children. About six thousand babies are born in the UK each year from IVF and intracytoplasmic sperm injection (ICSI) treatment.
Who is it for?
IVF was originally designed to help women with blocked or damaged fallopian tubes achieve live births. Since those early days it has come to represent the ultimate treatment for any form of infertility that fails to respond to other conventional treatment. The law as it currently stands in the UK allows any woman below the age of 55 years to have IVF treatment. Most units will however have their individual eligibility criteria and these typically restrict treatment to women below the age of 40 years and couples in proven stable relationships.
How is it regulated?
The Human Fertilisation and Embryology Authority (HFEA) regulates IVF treatment in the UK. The HFEA was established in 1991 to license clinics to offer this treatment, monitor the treatment, and regulate research that involves human eggs, sperm and embryos (fertilised eggs). It publishes an annual guide of clinics that offer IVF treatment and couples can obtain this free by ringing 0207 377 5077.
How is IVF performed?
IVF treatment involves a complex series of procedures:
- Initial assessment – this includes an interview with both partners as well as general and pelvic examinations of the woman. Blood tests are performed to determine the woman’s hormone levels, rubella status, blood count and blood group. The couple is also screened for transmittable infections including HIV, syphilis and hepatitis. The man’s sperm sample is examined to determine the sperm count, its movement, the proportion of normal sperm and if it contains antibodies. A swab from the vagina may also be taken from the woman to check for infection.
- Counselling of the couple – counselling can be of great help to the couple in understanding the treatment and should be available in all licensed units. Although not a compulsory requirement for treatment to proceed, couples are encouraged to utilise the opportunity for counselling. It will also help them come to terms with some of the difficulties they are likely to encounter.
- Stimulation of the ovaries – in the early days IVF treatment used to proceed in natural cycles without any stimulation and this contributed to poorer success rates. Treatment today proceeds in cycles where ‘controlled ovarian stimulation’ takes place to increase the yield of eggs. Stimulation is achieved using two types of medicines, one to suppress the ovaries so that the woman does not ovulate before this is desirable and the other to stimulate development of many eggs. These may be given as tablets, nasal puffs, or injections, and may be started at any time during the menstrual cycle. Pelvic ultrasound scans and blood hormone (oestrogen) tests are used to monitor the woman’s response to stimulation. Stimulation of the ovaries continues until the eggs are mature enough to be collected at which time another hormone injection is given to ripen them.
- Collection of the eggs – the eggs are usually collected from the ovaries by putting a needle into them through the vagina under ultrasound control, and sucking gently with a suction machine. General anaesthesia or sedation (pain-relieving medicine) is used for the procedure. The eggs may sometimes be collected by laparoscopy (telescopic examination of the inside of the abdomen and pelvis). The number of eggs that are collected varies from one woman to another depending on their response to stimulation. Most women will be able to return home on the day this procedure is performed.
- Mixing of eggs with sperm – the man will be required to produce a semen sample by masturbation on the day of the egg recovery. A three-day period of abstinence from sex or masturbation is advised to ensure the sperm are of good quality. The sperm are washed in a special fluid to select out the best quality ones and these are then mixed with the eggs. The mixture is left overnight till the next morning when it can be seen how many of the eggs have been fertilised by sperm.
- Replacement of embryos into the womb – the culmination of IVF treatment is the replacement of embryos into the womb. This is usually done two or three days after the egg recovery but can take place on any day up to five days after egg recovery. The embryos are gently sucked into a soft small tube that is passed almost to the top of the womb through its neck and injected there. This does not usually require any anaesthetic or sedation. The number of embryos that are replaced each time depends on the regulations in place in the country concerned. The maximum number that can be replaced each time in the UK is three, but usually two and sometimes only one is replaced to reduce the chance of multiple pregnancies (such as twins and triplets).
- Afterwards – women are advised to take things easy following replacement of embryos but there is usually no need to take time off work. Hormone injections or pessaries (vaginal tablets) are given afterwards to help the development of the embryos. If the treatment is not successful a period will usually begin between 7 and 14 days after the replacement. Women who have not had a period by this time may be offered urine or blood tests to detect an early pregnancy and if this is positive, an ultrasound scan may be performed three weeks later for confirmation.
- IVF treatment involves a long process that may take up to 6 weeks from start to finish and even longer to know if it has been successful or not. Appreciation of and adequate preparation for this will help couples cope with the often rigorous demands of the treatment schedules.
How successful is it?
The technique of IVF has made it possible for many couples to fulfill their hopes of having children. The chance of IVF succeeding is improved in younger women (less than thirty years old), following previous pregnancies and in couples whose difficulty with conceiving has only been short lasting. IVF success is measured professionally by pregnancy and life birth rates and these can vary widely around the world.
The average chance of a couple achieving a pregnancy from any one cycle of IVF treatment in the UK is about 2 in 10. This varies widely from 4 in 10 in some units to 1 in 10 in others. The average chance for each couple can go up to about 6 in 10 after four cycles of treatment. The HFEA guide provides a useful source of this information for couples and their doctors may be able to help them in choosing appropriate units.
What can go wrong?
About 3 out of 4 women will complete this treatment without any difficulties or problems. Some common difficulties or problems include:
- Poor response to stimulation – this may affect about 1 in 10 women. It causes the development of very few or no eggs at all and may lead to cancellation of treatment cycles.
- Excessive response to stimulation – this can result in a condition called ‘ovarian hyperstimulation syndrome’ that affects up to 1 in 10 women. It is fortunately mostly mild. It causes pain and bloating of the abdomen, vomiting, shortness of breath and tiredness. Admission to hospital may occasionally be needed for its treatment. Very severe cases may become life threatening, but this is rare.
- Injuries during egg recovery –- the needle used for the egg recovery may cause injury to the organs in the pelvis (such as the bladder, intestines, and blood vessels), but this is extremely rare.
- Pelvic infections – there is a risk of this following the egg collection and severe cases may result in pelvic pus collection. It usually causes the woman to become ill with fever and abdominal and/or pelvic pain. Antibiotics are used in its treatment and pelvic pus collection will need to be drained by surgery.
Human Fertilisation and Embryology Authority (HFEA) 30 Artillery Lane London E1 7LS Tel. 0207 377 5077
PROGRESS Campaign for Research into Reproduction 140 Gray’s Inn Road London WC1X 8AX