Combinations of drugs, given by injection, are used to stimulate egg production over a period of two to five weeks. A drug acts on the ovary to make it produce more eggs than it normally does and the other drug stops ovulation. On the day after the last injection, 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 between clinics).

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.

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, prepared and put with the eggs. The specialists can usually tell if fertilization has taken place after twenty-four hours.

If the eggs have fertilized 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 more than one embryo into the womb. Transferring two or three embryos into the womb (the most allowed by law in the UK) gives a better chance of a baby than one embryo does, but also gives a chance of more than one baby developing.

These options and possibilities should be discussed with your fertility clinic. Any healthy embryos that are not transferred can be frozen in liquid nitrogen. Normally written consent is required for this. About two weeks after the embryos have been placed in your womb you can carry out a pregnancy test.

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.

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 are having treatment. 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.