A “male Pill” could be as effective as condoms and its female equivalent, according to a major study.
May 4, 2009
Researchers were able to achieve a 99 per cent sucess rate by injecting men with testosterone in a trial that they claim is the largest so far conducted anywhere in the world.
The findings could re-invigorate interest in the method of preventing pregnancy, which has stalled in recent years.
Scientists have been searching for a male Pill for almost two decades.
However, progress has been slow, in part because of a lack of interest from big pharmaceutical companies to carry out large-scale trials and also because of a lingering belief that many women would not trust men to take the pill.
Although there have been several attempts to create a male version of the Pill, the only options men currently have to limit their fertility are to use condoms or to have a vasectomy, which is often irreversible.
The latest research, conducted in China, tested the testosterone injections on 1,045 healthy and fertile men, aged between aged 20 and 45.
All of the men who took part in the study had fathered at least one child within the previous two years and none of their partners had fertility problems.
Over two years the injections were 99 per cent successful, researchers found.
After the study ended all of the men, bar two, saw their fertility levels return to normal.
“For couples who can not, or prefer not to use only female-oriented contraception, options have been limited to vasectomy, condom and withdrawal,” said Dr Yi-Qun Gu from the National Research Institute for Family Planning in Beijing.
“Our study shows a male hormonal contraceptive regimen may be a potential, novel and workable alternative.”
However, he warned that larger tests were needed to determine the long-term safety of the injections, particularly on men’s hearts and prostate glands.
The findings were published in the The Endocrine Society’s Journal of Clinical Endocrinology & Metabolism (JCEM).
Earlier this year scientists said that they were a step closer to developing a male Pill after they identified a rare defective gene which can cause infertility.
Developing a drug which could target healthy versions of the gene could be an effective contraceptive.
Elaine Lissner, from the Male Contraception Information Project (MCIP) in San Francisco, said: “This new formulation appears to be a success.
”However, hormonal male contraceptives seem to work differently in Chinese and Caucasian men.