Male contraceptive jab is on its way

Posted by Emma Woollacott

And about time too. Scientists in China believe they have created a contraceptive injection for men that is as effective as the female pill.

BEIJING, CHINA - And about time too. Scientists in China believe they have created a contraceptive injection for men that is as effective as the female pill.

Chinese researchers injected 1,045 healthy, fertile Chinese men aged 20 to 45 years with a 500 milligram formulation of testosterone undecanoate in tea seed oil once a month for 30 months. The jab temporarily blocks sperm production by bringing about a drop in two regulatory brain chemicals, namely follicle-stimulating hormone and luteinising hormone.

Pregnancy resulted in just 1.1 per cent of cases - comparable to the best forms of female contraception. In all but two of the men, fertility returned to normal six months after the jabs were stopped. None reported any side effects.

While weekly testosterone injections were shown to be effective as long as ten years ago, it was felt that men were just too dozy to cope with the level of commitment that a weekly jab entailed. A monthly jab seems more practical, say the researchers. Combining the testosterone with the tea seed oil slows down its delivery, making monthly injections effective.

"The development of a male contraceptive injection, and potentially a male contraceptive pill, is a very positive step forward. Historically, women have tended to take more responsibility for sexual health since they bear the brunt of the consequences of unprotected sex," said Emily James, spokeswoman for family planning organisation Marie Stopes International. "New male-focused methods may encourage men to take on more of this responsibility, which we would welcome and encourage."

The study is the largest yet to look at testosterone as a method of male contraception. The researchers were based at several family planning research centres throughout China. The study appears in the Journal of Clinical Endocrinology and Metabolism, published by the Endocrine Society.

The injection is now in Phase III trials, meaning that it could be on the market within a couple of years.