A decade of IVF ‘miracle stories’ have created the impression that childlessness is a thing of the past, but, as Anna Kavanagh of the Midland Fertility Service explains, infertility treatment is still a gamble

On July 25, 1978, Louise Brown became living proof that conception could take place in a test tube. Many thousands of babies later, In Vitro Fertilisation (IVF) is almost routine, and it’s easy to assume that it provides the answer to all fertility problems.

The percentage of IVF treatment cycles which result in a birth is rising, according to the human fertilisation and embryology authority, which said between April 2000 and March 2001, 21.8% of IVF treatment cycles resulted in a birth, compared with 19.5% in 1998-99. That said, it's important to realise that IVF fails more often that it succeeds. Success rates do depend on your age however, and in 2004 were 28.1% for women under 35 years old, 21.9% for women aged 35-39 years, 17.5% for women aged 38-39 years, 10.4% for women aged 40-42 years, 4.2% for women aged 43-44 years and 1.4% for women aged over 44. Women over the age of 40 may therefore be advised to use donated eggs from a younger woman.

Success rates vary from clinic to clinic, so phone clinics in your area and ask for their most recent statistics for your age group and type of treatment. This may be IVF using standard insemination technique (which is described later) or it might be IVF using Intra-cytoplasmic Sperm Injection (ICSI). ICSI is used for sperm problems and the embryologist injects an individual sperm into the ‘heart’ of each egg, bypassing natural fertilization.

At the same time ask about the clinic’s frozen embryo transfer programme. A good programme will increase your chance of getting pregnant with each stimulated cycle of treatment.

What is IVF?

Basically IVF involves collecting eggs from the ovary, putting them together with sperm in a dish and, if those sperms fertilise an egg, putting the embryo or embryos that result into the womb.

The treatment

Every month women prepare several eggs in their ovaries, but usually only one is chosen by the body to be released into the fallopian tubes. With Natural Cycle IVF, the one egg your body produces is collected and fertilised, to avoid the side effects of drugs and prevent multiple pregnancy. As there is often a problem with natural egg production, however, it is more usual to stimulate the ovaries with drugs to produce more than one egg. This gives a better chance of collecting at least one which is healthy.

Combinations of drugs given by injection are used to stimulate egg production over a period of two to five weeks. One type of drug (gonadotropin releasing hormone analogue) suppresses your natural hormones to control your ovulation cycle, while another type of drug (a gonadotropin) acts on the ovaries so they produce more eggs than normal. On the day after the last injection of gonadotrophins, an injection of the hormone hCG (human Chorionic Gonadotrophin) is given. This matures the eggs, which should be ready for collection about 35 hours later (this may vary slightly between clinics).

Collecting and fertilising the eggs

The procedure to collect the eggs takes about half an hour and can be done under a general anaesthetic, although many clinics prefer to use sedation and painkillers. A fine needle is passed through the back of the vagina and into the ovary. The fluid from each follicle is sucked into tubes and examined by the embryologists who look for eggs. Each portion of fluid is examined in turn until every possible egg has been collected.

In a woman who is at risk of overstimulation of the ovaries (eg because she has polycystic ovaries, or has experienced hyperstimulation syndrome before), fewer drugs are given and the eggs collected while still immature. The eggs are then allowed to mature in the laboratory. This technique, called in vitro maturation (IVM), is not yet available in all clinics.

The next stage is to put the sperm with the eggs. The semen needs to be produced shortly before the eggs are collected. The sperm are then washed and prepared and put with the eggs. The specialists can usually tell if fertilization has taken place after twenty four hours.

Replacing the eggs in the womb

If the eggs have fertilised and are developing normally, they will be put back into the womb two to three days later. The procedure is simple. A plastic tube is passed through the cervix (the neck of the womb) and the embryos put high into the womb.

To give the best chance of pregnancy, most IVF units put two embryos into the womb. This gives a better chance of a baby than transferring one embryo, but does give a chance of more than one baby developing. As the health risks for babies and mother are greater with a twin pregnancy, you may be advised to have only a single embryo transferred if you are under 35 years of age, have good embryo quality, few previous failed IVF cycles, and a good chance of conceiving this way. Your clinic will discuss these options with you.

Any healthy embryos that are not transferred can be frozen in liquid nitrogen for up to ten years but you must give your consent in writing for this.

About two weeks after the embryos have been put into your womb you can carry out a pregnancy test.

The risks

Although IVF is a standard treatment it does carry some risks. 2 % of cycles may be complicated by infection, bleeding after the procedure or ovarian hyper-stimulation syndrome (OHSS). This occurs when the ovaries respond too well to the fertility drugs. OHSS can be mild and may only cause a bloated feeling, however, more severe cases need hospital treatment, to deal with the loss of fluid from the circulation.

Emotional stress

You do need to be aware that IVF is emotionally stressful for both the man and the woman. Couples find it extremely disappointing if the treatment does not work and you may need emotional support while you’re having treatment. Your clinic may well offer counselling, hypnosis or training in relaxation techniques and possibly a support group. The stress that IVF treatment involves is hard to come to terms with but if a cycle of treatment fails, specialists can help plan another course, should you want it and feel able to cope emotionally as well as financially.

For more information see other related articles:

The cost of IVF

The influence that age has on fertility.