Scientists reveal male contraceptive injection (Vasalgel) that block sperm for up to 12 months

Male birth control has long been a dream of women worldwide. Other than condoms and vasectomy, men currently have few options of birth control.

And so, the burden of taking contraceptive pills – or having devices implanted – has rested on the shoulders of women for decades.

But now, scientists have revealed a male contraceptive injection could soon be available.

The shot, called Vasalgel, is non-hormonal and long-acting – and has been shown to block sperm for up to 12 months.

Clinical testing of the shot is set to begin this year, according to the non-profit Parsemus Foundation, of Berkeley, California.

Dr Elaine Lissner, executive director of the foundation, said: ‘Contraceptive development is a hugely expensive project.

‘But this is not just another early-stage lead; we’re so close on this one. It’s time to finish the job we’ve started.’

There are more than 85 million unplanned pregnancies annually across the globe.

Condoms are widely available and useful in preventing disease when used correctly.

However, they have an 18 per cent yearly pregnancy rate in typical use, according to Parsemus Foundation.

And while vasectomy is effective – it is generally considered permanent.

Therefore, currently, there are no long-acting, reversible contraceptives available for men.

Yet, the demand for new contraceptive methods is strong and growing, with international surveys indicating that the majority of men would be willing to use new male contraceptive methods.

Scientists have discovered several possible methods to control male fertility in the past few decades – but none have made it to market thus far.

Furthermore, research has focused on hormonal approaches – even though many men favor non-hormonal options, due to side effects and safety risks.

But in a new study, Parsemeus confirmed that Vasalgel has the potential to fill the gap in the male contraception market.

The shot consists of styrene-alt-maleic acid (SMA) that is dissolved in dimethyl sulfoxide.

Vasalgel could be the first long-acting, non-hormonal, potentially reversible male contraceptive to reach market, researchers noted.

Scientists conducted an initial study on 12 rabbits – injecting the gel into their vas deferens (a duct in the male reproductive system).

Once injected into the vas deferens, the material forms a hydrogel.

The implant stays in a soft gel-like state, with the ability to flex and adhere to the walls of the vasa deferentia.

The hydrogel also allows transit of many water-soluble molecules – but not larger structures, such as sperm.

The study found that the rabbits had no sperm in their semen as early as 29 days post-injection.

The findings also confirmed that the contraceptive effect lasted the entire 12-month study period.

Lead study author Dr Donald Waller, of Prelabs LLC and a professor at the University of Illinois at Chicago, said: ‘Results from our study in rabbits were even better than expected.

‘Vasalgel produces a very rapid contraceptive effect which lasted throughout the study due to its unique hydrogel properties.

‘These features are important considerations for a contraceptive product to be used in humans.’

The scientists were able to remove the gel to return the flow of sperm – or reverse the contraceptive effect – as well.

The first clinical trial in men is scheduled to launch later this year – and the ultimate goal is for Vasalgel to be available worldwide, at an affordable cost.

The study was published in the journal Basic and Clinical Andrology.

Read More: Mail Online UK