As a man, if you're not a fan of condoms and don't really want to commit to a vasectomy, you're pretty much out of options when it comes to birth control. Now, researchers have developed a new compound that slows down sperm to the point where they can no longer swim, potentially paving the way for a male contraceptive that doesn't affect natural hormones and is reversible.

Although the "Pill" has been an option for women for decades, scientists have only fairly recently made strides towards a similar product for men. These include ultrasound pulses to kill off sperm, injecting a gel into the vas deferens that blocks them and drug compounds that hinder sperm development or movement.

The latest idea, a compound known as EP055, falls into that last category. Developed by researchers at UNC-Chapel Hill and Oregon Health and Sciences University, EP055 binds to certain proteins on the surface of the sperm and disrupts their motility.

"Simply put, the compound turns off the sperm's ability to swim, significantly limiting fertilization capabilities," says Michael O'Rand, lead investigator on the study. "This makes EP055 an ideal candidate for non-hormonal male contraception."

The team tested the compound on male rhesus macaques, giving the animals increasing doses of the drug intravenously. Sperm motility in the animals was completely disrupted 30 hours after the injection, and the effects were long-lasting but reversible. Less than three weeks after the treatment the macaques had all regained normal sperm motility, which bodes well for a potential pill that can be taken regularly, and simply stopped if you want to start trying for kids.

"At 18 days post-infusion, all macaques showed signs of complete recovery, suggesting that the EP055 compound is indeed reversible," says Mary Zelinski, co-investigator on the study.

Of course, the compound isn't ready in its current form. A daily jab isn't going to be very popular, but the researchers say they've already started testing a form of EP055 that can be taken as a pill. Next, the team plans to carry out mating trials to test whether the compound does prevent pregnancy in macaques.

In the meantime, a drug known as DMAU has already proven promising in Phase 1 human clinical trials.

The new research was published in the journal PLOS ONE.