In 2016, news broke that a promising study on a male birth control shot was stopped because too many of the participants were dealing with side effects, including depression and mood changes. Many uterus owners who have had to deal with similar side effects thanks to hormonal birth control understandably rolled their eyes. But the failure of that clinical trial was more about the frequency and severity of the side effects (which included mood disorders in about 20 percent of participants than it was about men being wimps.

The reality is that developing male birth control is a medically tricky proposition. However, the responsibility of preventing pregnancy has historically fallen on women's shoulders, and this means women have also borne the burden whenever access to birth control has become politicized and restricted. Yes, condoms work in the short-term. Yes, vasectomies can take care of unwanted fertility, too. But it would be pretty nice if there were a reversible male contraceptive — so why exactly don't we have one yet? It turns out that the answer is about more than just scientific progress. Here's what's really going on, according to the experts.

How would reversible male birth control actually work?

First, a little anatomy refresher: Female hormonal contraception, including the pill, essentially works by tricking your ovaries into thinking you're already pregnant.

"During pregnancy, female hormones increase dramatically and, among other things, they signal the ovary to stop producing eggs," David Sokal, board chair of the nonprofit Male Contraception Initiative (MCI), tells Allure. "The development of the pill in the 1950s took advantage of this natural process." While the amount of hormones in the pill is lower than the amount that would be in your body if you were actually pregnant, it's still high enough to signal your ovaries to pump the brakes and not release an egg.

A male birth control pill, meanwhile, "would essentially be something that a man would take that would suppress sperm production," Los-Angeles-based urologist and sexual medicine specialist Joshua Gonzalez tells Allure.

As Sokal points out, though, men don't have sperm production cycles: The testes just continuously produce sperm. Male birth control researchers are looking for a way to stop sperm production altogether using progestin, which is used in hormonal birth control for women. Progestin is the synthetic version of progesterone, a sex hormone that is produced mainly in the ovaries. The progestin route is promising, but not without its side effects. Mood changes caused by hormonal birth control might be more severe in men than they are in women, Sokal says.