We know very little about the effects of man commonly used drugs on fertility. In most countries the testing of drugs includes toxicity studies of the reproductive organs of animals, but there are no safety checks made on the effect of these drugs on human gonads.

Impaired semen quality has been detected by chance during the use of drugs that were given routinely before their toxic effect was known. For example, sulphasalazine, which is used to treat inflammatory bowel diseases, can drastically reduce semen quality. Although the effects seem to be reversible when this drug is used in moderate doses for a limited time, the production of sperm may be permanently impaired. Some drugs used to treat high blood pressure, such as beta-blockers, may cause impotence. Anabolic steroids, which are widely used by athletes and body builders, have severe side effects on reproduction, including low sperm count and no sperm. The numerous cytotoxic drugs which are used to treat cancer and autoimmune disease can damage gonadal function, and some of them, such as cyclophosphamide, procarbazine and cisplatin, can cause gonadal failure. There also may be striking differences between the effects of the same drug on men and women (The Lancet, June 11, 1994).