A new type of reversible, non-hormonal male contraceptive has been found to work reliably in primates

Known as Vasalgel, the contraceptive works by blocking the vas deferens (the tube that sperm travels down) with a flexible, spongy, hydrogel material that allows bodily fluids to pass while blocking sperm cells.

The gel can then be subsequently flushed from the vas deferens, restoring sperm flow.

Vasalgel was found 100% effective at preventing conception among a group of rhesus monkeys for more than a year.

“Men’s options for contraception have not changed much in decades. There’s vasectomy, which is poorly reversible, and condoms,” Catherine VandeVoort, of the California National Primate Research Centre and the study’s lead author, told The Guardian.

“If they knew they could get a reliable contraceptive that could also be reversed I think it would be appealing to them.

“They wouldn’t have to worry about it on a day-to-day basis. This would be more aking to an IUD in women,” she said.

The funding organisation behind the study says it plans to start human trials as soon as funding is secured based on the positive results.

“One of the great things about the monkey model is that the male reproductive tract is very similar to humans and they have even more sperm than humans do,” VandeVoort told The Guardian.

“Chances are, it’s going to be effective in humans.”

It may be welcome news for those who were disappointed last year when a male hormonal contraceptive jab was found to be as effective as the female pill, but was discontinued after about 6% of participants experienced unwanted side effects, including depression, muscle pain, mood swings, acne and heightened libido.

In contrast to a male hormonal contraceptive injection, the Vasalgel procedure does not interfere with sperm production and hormone levels in the body remain unchanged, meaning such side-effects are not an issue.

As with a vasectomy, sperm continues to be produced in the testes, but rather than being ejaculated, it dissolves and is naturally absorbed by the body, writes The Guardian.

However men won’t be pleased to know that the method of placement is through the use of a catheter.

Professor Rob McLachlan from the Hudson Institute of Medical Research and Andrology Australia told the Sydney Morning Herald that while the idea is “fantastic in principle”, it still critically needs to be tested on humans.

“Don’t expect an easy or quick answer,” he says, explaining that the cost and size of human trials are “massive”.

“You have to show it’s effective and safe and then you have to scale it up,” he says. “It’s a long journey – it’s a 10-year journey.”