Male birth control may soon be an easy pill to swallow, according to researchers at the University of Washington.

However, one big question remains: Will men take a male contraceptive, even if it’s easy to use?

The university’s experimental male oral contraceptive would be taken once a day and acts upon male sex hormones, including testosterone.

The pill, called dimethandrolone undecanoate (DMAU), reduces the levels of these hormones to amounts that are low enough to suppress sperm production.

“It’s challenging to give testosterone and similar chemicals like it by mouth because of their limited time in the bloodstream and associations with liver problems,” Dr. Stephanie Page, professor of medicine at the UW School of Medicine and the study’s senior investigator, told Healthline. “Our goal is to develop something that is very low in side effects.”

The study findings haven’t been published yet in a peer-reviewed journal. They were presented earlier this month at ENDO 2018, the Endocrine Society's 100th annual meeting in Chicago.

The results of the study were promising in their lack of significant side effects with test subjects.

“Sexual functioning, libido, performance — our analysis of the reports we received showed no difference in sexual health between the men taking the pill and those on a placebo,” Page said.

Of the test subjects who completed the study and were taking 400 milligrams (mg) of DMAU — the highest dose tested — few reported symptoms consistent with testosterone deficiency.

The subjects who were given the pill did have weight gains of between 1 and 3 pounds on average, according to Page.

“The weight gain and a small decrease in good cholesterol levels, HDL, are things we’re going to look at more closely in future studies,” Page says.

The current alternatives available to men for contraception, vasectomies and condoms, have limitations.

“Vasectomies are irreversible and condoms have a high failure rate — it’s 18 percent,” Page said. “Any product that males would take should have a 90 to 95 percent efficacy rate, comparable to the rate for the female pill. That’s critical.”

Would men use it?

Although the majority of men Healthline polled last year said they would not take a male version of the birth control pill, there are indications that social mores are changing.

This is especially true as younger generations look to share the responsibilities of contraception and family planning. “Single men are interested in controlling their own fertility,” Page said. “Men in families are interested in participating in spacing pregnancies as well. Young people are interested in contraception.”

“When the female pill was developed, gender roles were different. For women, pregnancy is a health risk,” Page added. “The need for contraceptives for women is and was different, but that doesn’t mean there isn’t a need for men.”

This new pill is different, too.

“The difference with the DMAU pill is that men didn’t say they felt awful when they were on it,” Page said. “There is still enough testosterone in the blood that all other parts that are male — hair, libido, muscle maintenance, low voice — all the male characteristics are maintained by what’s in the pill.”

The search for a male contraceptive

DMAU, or the male pill, is one of several male contraceptives in development.

Gels and injections, however, have not proven effective, or even desirable to men. Other forms of male contraceptives are nonhormonal.

“There are several methods of contraception in development that we support and promote,” Logan Nickels, director of operations and programs for the Male Contraceptive Initiative, told Healthline. “There are different formulations of hormone delivery systems like DMAU, but there are lots of different flavors of nonhormonal possibilities that will work.”

Nickels said that Vasalgel and Echo-VR, two surgical methods of male contraceptive that don’t have the permanence of vasectomies, show promise.

“The best estimate for a safe reversible contraceptive for men is 10 to 20 years,” Nickels said. “Vasalgel and Echo-VR are devices, so the approval process is on a shorter timeline [than a hormonal contraceptive]. It’s a long time before some guy could get a script for the pill and go get it.”

“But the best time to plant a tree was 20 years ago,” Nickels says. “The next best time is today.”

Regardless, the news of a promising male contraceptive is welcomed.

“This study is pretty exciting,” Nickels said. “It has the potential to promote the feasibility and ability of men to accept a male contraceptive pill. We’re in support of any male contraceptive that can be an efficient, low-barrier entry into the family planning space.”

Page hopes the pill would have widespread use, with a high adoption rate.

“Men are interested in contraception,” Page said. “Choices for contraception should be available to men, too. Some women can’t take the pill and men wish to share the contraception burden.”