Are we nearing the end of the long road to hormonal birth control for men?

As the impacts of overturning Roe v. Wade continue to lead to big questions about reproductive rights, a parallel story recently caught our eye. A reversible contraceptive treatment for men may soon be a reality. A hormonal birth control method for men is now in clinical trials.

Dr. Stephanie Page is a professor and endocrinologist at the University of Washington School of Medicine. She has been working in contraceptive clinical trials for more than 20 years and is leading the trial here in Seattle. She told KUOW’s Kim Malcolm about the results so far.

This interview has been edited for clarity.

Kim Malcolm: How does this male birth control method work?

Dr. Stephanie Page: Hormonal birth control for men works very similarly to the birth control pill or other hormonal methods for women. In this case, instead of using estrogen, we're giving men a combination of testosterone and a progestin. In women, we’re blocking ovulation. In men, we're blocking the production of sperm. The beauty of hormones, as for women, when we take them away, the man starts to make his own hormones again. And it's entirely reversible.

How are these forms of male birth control given? What are the options?

We are working on hormonal methods that could be delivered either by a gel or by a long-acting injection. We're also working on a pill, which would be very similar to the female birth control pill.

How long will these trials last, and when do you expect to have final results?

We anticipate that it will finish in about a year and a half. The second trial, involving about 5,000 couples, would be next. That will take another three or four years. The hope would be to get this gel on the market in five to seven years.

What kinds of side effects have the men found, if any?

Only a minority of participants experience them. Plenty of men in this trial have absolutely no side effects whatsoever.

And I understand some of the men have reported these as being positive side effects.

Exactly, particularly with regards to mood and libido. Some men have actually experienced an increase in libido, which most men view as a positive.

Have there been other surprises that came up for the people participating in this trial, or for you?

I think one of the most exciting things is that we anticipated that putting a gel on every day would be both difficult and sort of tiresome for men to do. In fact, most of the men work it into their routine fairly easily. The gel rubs in well. We haven't seen a lot of skin side effects. I think the ease of use has been better than we anticipated.

Perhaps the most encouraging thing is how many of the couples who finished the study are really sort of disappointed that they can't use the product anymore, don't want to go back to their old methods, and want to know when they're going to be able to start buying it.

If this comes through, it holds out the promise that men will be able to control their fertility in a way that lifts some of that burden from women. Why has it taken this long to find a form of reversible male birth control?

The first reason is that there was a social imperative for women to control their own fertility. Appropriately, the majority of investment and research went into female contraceptives more than 60 years ago. That put us a little bit behind.

The second is the biology. Women ovulate one egg a month. Men are making literally millions and millions of sperm every day. We had to figure out if we needed to block all the sperm, if getting a few through was going to still be effective as a contraceptive, and it turns out that it is.

I wonder what you're making of the changes to reproductive care after the decision by the U.S. Supreme Court to overturn Roe v. Wade, and what role this new method of male birth control might play in the future.

As a physician who is a feminist and a believer in equal rights, there is nothing that is more devastating than the recent decision. Contraception will never replace entirely the need for safe abortion. We need to have that available when things go wrong because they always do at some point.

But nonetheless, unplanned pregnancy rates in this country have been pretty stagnant at 40% over the last 20 to 30 years. That's despite the introduction, importantly, of a lot of new female methods of contraception. So, male contraception could be a real game-changer in making a dent in unplanned pregnancy. And now more than ever, we need to really attack unplanned pregnancy as a problem, make sure that contraceptives are available, and engage our entire population in making sure that every pregnancy is a planned pregnancy.

Listen to the interview by clicking the play button above.