In 2018 US researchers will trial the effects of a completely new kind of male contraception: a gel applied like lotion that prevents the production of sperm.

The product, Vasalegel, is massaged into the arms and shoulders so it absorbs through the skin and into the bloodstream. The gel uses two synthetic hormones – testosterone and progestin – to stop the testes from making enough testosterone to produce normal levels of sperm.

The synthetic testosterone in the gel balances hormone discrepancies, meaning there should not be any bad side effects, Metro reported.

However, since the trials are still in the early stages, there is no chance of it being available any time soon. The clinical trial needed to ensure the gel is a valid form of contraception will start in April and run for four years. Some 400 couples have volunteered for the study, with men asked to take home a pump bottle of the gel and rub around half a teaspoon of it on to their upper arms and shoulders every day.

Daily use is vital to the study as the gel can suppress sperm levels for around 72 hours, so a few missed days will have an effect.

Researchers will regularly record the men's sperm levels to see if they drop to less than one million per ml of semen – the level required to effectively prevent pregnancy. During this time, their female partners will be using contraception alongside just in case.

Once the men's sperm count is low enough, their partners will come off their contraceptives and the couples will use the gel as their only form of birth control for a year.

Who knows, if these go well then there might be a revolutionary form of birth control available in a few years time.