When a doctor can find no definite physical reason for a couple's infertility, he looks for subtler clues in the patients' environment. Such investigation might even lead him to ponder new forms of contraception. Now, in a letter to the British Medical Journal, Dr. Emanuel Saphier, a general practitioner in the London suburb of Sutton, tells of one successful case of medical sleuthing and prescription. The patient, a childless man who rode a bicycle 21 hours a day, was told to give up his cycling.
Why blame the bicycle? Dr. Saphier knew that sperm production can be reduced by tight clothing that...