(The Hill) – A new male contraceptive was found to be 99% effective when tested in mice, according to research presented at a meeting of the American Chemical Society (ACS) on Wednesday. Gunda Georg, is a medicinal chemist who leads the University of Minnesota lab conducting the research.

Georg said that human testing of the nonhormonal male contraceptive could begin as soon as the third or fourth quarter of 2022, according to a press release from the ACS. Abdullah Al Noman, a graduate student involved in the research said “Scientists have been trying for decades to develop an effective male oral contraceptive.”

Currently, no approved male birth control bills are on the market, he added. The ACS noted that the majority of male birth control pills in the works use hormones to target testosterone, which could potentially cause side effects such as weight gain, depression, and increased low-density lipoprotein cholesterol levels.

“We wanted to develop a non-hormonal male contraceptive to avoid these side effects,” Noman said.

When given orally to male mice for four weeks, the compound researchers tested was found to be 99 effective in preventing pregnancy in female mice. No observable side effects were detected, and male mice were able to reproduce within four to six weeks after they stopped receiving the compound.

“Because it can be difficult to predict if a compound that looks good in animal studies will also pan out in human trials, we’re currently exploring other compounds, as well,” noted Georg.