Hormone replacement therapy for women could hold the key to creating a male contraceptive pill, scientists revealed today.
Researchers found that compounds used in HRT and the female pill could have a contraceptive effect on men when used alongside testosterone.
However the team from the University of Manchester and Leeds General Infirmary said that it could take 10 years to develop and market a male pill.
A number of trials are looking at alternatives to condoms, vasectomy and abstinence.
The latest studies, led by Professor Fred Wu, found that synthetic progestins in HRT - called tibolone and nomegestrol acetate (Noma) - suppressed the hormones that stimulate the production of sperm. Noma showed particular promise as it had no adverse metabolic effects. Other male contraceptives in production have been shown to decrease good HDL cholesterol, which protects against heart disease.
Professor Wu said it would be easy to use, "just one pill a day and a testosterone injection once a quarter".