Contraceptive jab for men a step closer as tests prove 99% successful

Published on Monday 4 May 2009 21:57

MEN in Scotland could soon be offered a contraceptive jab after a major study found only one in 100 males using the injections conceived a child.

Researchers hope the testosterone injection could revolutionise family planning methods, since the form of birth control proved highly effective in over 1,000 men.

Doctors discovered just over one in 100 men conceived a child over a period of two years, which is considered a very good result given that no contraceptive is 100 per cent effective. Each year, between 1-2 per cent of women on the Pill still get pregnant.

The injection was tested on a group of healthy, fertile men aged 20 to 45. Each had fathered at least one child in the previous two years and female partners were aged between 18 and 38 with no reproductive problems.

Dr Yi-Qun Gu, from the National Research for Family Planning in Beijing, which conducted the research, said: "For couples who cannot, or prefer not to use only female-oriented contraception, options have been limited to vasectomy, condom and withdrawal.

"Our study shows a male hormonal contraceptive regimen may be a potential, novel and workable alternative."

The men were given monthly 500 milligram injections of testosterone undecanoate (TU) in tea seed oil over a period of two and a half years. No serious side effects were reported and the men's fertility returned to normal in all but two participants after the treatment was stopped. Testosterone injections lead to a cut in levels of two regulatory brain chemicals, which disrupt sperm production.

Results from the trial, the largest effectiveness study of a testosterone-based male contraceptive ever undertaken, will appear in the June issue of the Journal of Clinical Endocrinology and Metabolism.

Dr Gu said further tests were necessary, adding: "Despite the present encouraging results, the long-term safety of this hormonal male contraceptive regimen requires more extensive testing with a focus on cardiovascular, prostate and behavioural safety."

Last night, Susan Seenan, from Infertility Network Scotland, said a male jab could offer real alternatives for birth control.

She said: "Early studies appear to show that this could be an effective contraceptive for men, offering an alternative to the more final option of a vasectomy.

"Some men who have had a vasectomy later find that their circumstances change and they are then faced with the difficulties of being unable to have another child.

"Vasectomy reversal can be difficult and have limited success and although further research is needed, anything which can save couples from the emotional impact of infertility is welcome news."

This latest piece of research could prove to be a major breakthrough in providing another contraceptive for men after progress on a male pill stalled in recent years.

Edinburgh University researchers have been among those testing a hormonal treatment to stop sperm production, allowing men to take responsibility for birth control.

But in July 2007, it was reported that work had come to a standstill as plans to launch a male pill had been hit by a lack of cash from drug companies.