It is estimated that approximately one in every eight couples in this country are affected by infertility.

If a pregnancy does not result after two years of regular intercourse then a couple should present themselves to their GP for evaluation. Regular intercourse need only occur twice a week.

The commonest cause of infertility in males relates to a low or absent sperm count or poor sperm mobility. In females there can be failure to ovulate or tubal disease. Unfortunately in up to 25% of couples no obvious cause is found.

In males it is important to check a sperm count. This may need to be repeated on one or two occasions. In females a full medical history and examination is necessary and a blood test for serum progesterone and other hormones should be checked. The serum progesterone level is useful for identifying whether or not ovulation is occurring. When these basic investigations are complete, referral to a specialist will usually be necessary.

Where a sperm count is inadequate, pregnancy can still arise but the chances are low and assistance may be required. If there is a total absence of sperm the alternatives may be to consider artificial insemination with donor sperm or adoption. Where a female is not ovulating, drugs can be used to stimulate ovulation. Tubal surgery for blocked or diseased tubes can yield very disappointing results.

Where no cause for infertility is found, where tubal disease is not amenable to surgery, where ovulation stimulating drugs fail to result in pregnancy or where a sperm count is low, then consideration may be given to in-vitro fertilisation. With this technique the female's ovaries are stimulated to produce many eggs. The eggs are then harvested from the ovaries using a fine needle guided by an X-ray. The eggs are then incubated with the husband's sperm and the fertilised eggs are then introduced into the womb. Success rates for this technique vary between different centres from 15-25%.