A male contraceptive pill could be on the horizon, as a new scientific study reveals a compound capable of blocking sperm production in mice which could one day be used by humans.

Scientists from the Dana-Farber Cancer Institute and Baylor College of Medicine have discovered a tiny molecule that yields a quick yet perfectly reversible decrease in sperm count in rodents.

The beacon of gender equality, the compound, known as JQ1, infiltrates male testes cells and temporarily made the mice in the experiment infertile as the dose produced fewer and less mobile sperm. The result is non-hormonal birth control; furthermore the effects of it can be reversed or stopped anytime. ”Within one to two months [after discontinuing the drug], there was complete restoration in testicular size, sperm number, sperm motility and – importantly – fertility,” Dr. James Bradner, an author on the study told the Huffington Post. “The litter size was normal, and there were no obvious, adverse symptoms in these animals,” he added.

Dana Farber researchers originally created the JQ1 as a means to block out cancer causing genes, but the results from the initial testing made them seek advice from contraceptive specialists at Baylor to see if the mice formula could be repeated in men. In the new study, published in the Cell journal, researchers showed how JQ1 effectively penetrated the blood-testis boundary in mice, preventing sperm from maturing.

The conclusion was unexpected because few drugs on the market are capable of penetrating the protective gatekeeper known as the blood-testes barrier that safeguards the testicles from matter floating around in the blood stream.

“These findings suggest that a reversible, oral male contraceptive may be possible” Bradner explained.

It’s “a breakthrough new approach,” stating that there has not been a new reversible male contraceptive sine the creation of the condom, William Bremner from the University of Washington in Seattle, told Reuters.

“It’s exciting basic science that provides a new approach to think about how a contraceptive for men might be designed,” says Bremner. “At the same time, it’s a long ways from being in clinical trials in men, let alone being on pharmacy shelves.”

A contraceptive pill for women has been around for decades, but an equivalent for men has yet to arrive. Vasectomy is the only option for birth control after condoms.

Numerous research teams have developed hormonal pills that are effective, but they disrupt the hormone balance in men, and drug companies have not yet decided to cash out on this approach, Bremner said.

The US market for female birth control pills amounts to $3.5 billion a year according IMS Health Inc, Condom sales amounted to $430 million last year.

Previous attempts at male contraception focused on using a combination of testosterone and progestin intake to lower the sperm count in men, which would reduce the risk of pregnancy.

In the last decade, the focus in male contraceptive research has seen a shift from hormonal toward non-hormonal agents. Last year, a major trial of hormone-based male contraception was stopped because of bad side effects, including depression.

The author of the study has cautioned that even though the new findings are promising, they are just preliminary. “It will take some years of research,” Bradner told the Huffington Post “It’s just completely unpredictable. But we’re working very hard on this problem.”