A POLYESTER jockstrap has been designed by researchers from Egypt as a new method of contraception for men. Writing in Contraception, they report that the garment can temporarily abolish sperm production. The jockstrap is tailored to fit, worn day and night and changed only when soiled. The researchers found that the sperm counts of 14 volunteers dropped to infertile levels after an average 140 days' wear. None of their partners conceived during the 12-month study. The men's sperm counts climbed back to normal an average of 157 days after discarding the sling.

The polyester sling works by raising scrotal temperature and generating static electricity, both of which inhibit the production of sperm.