Birth control options have changed a lot over the past few decades. The female birth control pill, in its various forms, has long been considered the gold standard in preventing unwanted pregnancies (besides abstinence, of course), but figuring out how to make a similar pill for men has proven very challenging.

Now, researchers presenting their work at the annual meeting of the Endocrine Society in New Orleans have revealed that a new male birth control pill is showing promise, and it’s already passed “safety and tolerability” tests. The tests showed that the drug was able to suppress sperm production while leaving libido intact.

The drug is called 11-beta-MNTDC (which stands for 11-beta-methyl-19-nortestosterone dodecylcarbonate, in case you were wondering). It has a dual-action function that researchers say has proven suitable for the 30 men who volunteered to test it. In testing, which included a smaller sample of men who were randomly selected to receive a placebo instead of the drug, those who took it said they did not experience any severe side effects.

One of this biggest issues with testing of male birth control pills in the past was a dramatically decreased sex drive among the men who tested it. This is obviously something of a deal breaker for many. 11-beta-MNTDC is different, and only a handful of the men who tested it said they experienced a mildly decreased sex drive. Other minor side effects included reports of headaches and acne, but none were severe enough for the volunteers to stop taking the drug.

Unfortunately the testing couldn’t determine the overall effectiveness of the drug in the long term. The medication did dramatically decrease testosterone in the subjects, suggesting that it would be adequate in curbing sperm production, but the 28-day testing window is well short of the 60-90 days that would be needed for the sperm reduction to be noticeable.

Science isn’t quite there yet, but the research is definitely promising. The researchers predict that male birth control should be readily available within the next decade.