Sixty-four years after the first female contraceptive pill was approved for National Health Service (NHS) use in the UK, science is finally on the verge of producing one for men.

Animal studies show the experimental tablet – currently known only as YCT-529 – could effectively switch off sperm production, and a recent trial with 16 healthy men found it did not cause serious side-effects.

The next step is studies on hundreds of men, to establish whether it is effective at preventing unwanted pregnancies. If successful, the world’s first male contraceptive pill could be available within three years.

The quest to find a male contraceptive pill has been a long one. Most attempts have focused on methods that suppress the activity of hormones, called gonadotropins, which stimulate the production of sperm.

But this can dampen libido and cause adverse effects, such as muscle weakness and hot flushes. YCT-529 is generating excitement among fertility scientists because it does not rely on disrupting hormones in order to achieve birth control.

The Pill works by blocking the effects of a protein called retinoic acid receptor alpha, which plays a crucial role in sperm formation.