Does Birth Control Gel For Men Actually Work? What We Know So Far

Science has made great advances when it comes to different types of birth control. From condoms and vaginal rings to intrauterine devices (IUD) and hormonal birth control pills, the list is pretty impressive. 

One thing remains true, however. Women have more options than men. Experts think there are many reasons behind this. One is simple biology and numbers. Males produce a much larger amount of reproductive cells (sperm) when compared with women who only release an egg or two a month. So it's a lot easier to focus on effective contraception with a smaller number. As explained by a reproductive biologist who studies male contraceptives at Washington State University, Michael Skinner (via Vox), "The male produces hundreds of millions of sperms every day, and when the ejaculate comes out, there are 250 million sperm." Another reason has to do with insufficient funding for trials to test out male contraceptive methods, per researchers. 

But something seems to have shifted on that front, at least with a new hormonal male contraceptive gel that men can apply to their arms and shoulders every day to prevent pregnancies. Developed by the National Institutes of Health's (NIH) Contraceptive Development Program and Population Council, the gel contains two hormones — Nestorone (segesterone acetate) and testosterone. It has shown encouraging results in an ongoing phase 2 clinical trial in reducing sperm count to levels that are low enough to prevent pregnancy. Here's how it works. 

Birth control gel for men: How it works

If you've ever wondered about what would happen if a man took birth control, you might have your answer with this gel. The gel, known as Nestorone/Testosterone, is said to have the same approach as birth control pills for women. Nestorone is a progestin and it works by blocking the production of testosterone in the testes. This, essentially, reduces the production of sperm. 

Interestingly, the contraceptive gel also contains testosterone. While that might seem counterproductive at first glance, there is a reason behind it. It is important for men to have a certain level of testosterone in their system to maintain a healthy sex drive. Apart from libido, testosterone serves other functions like regulating bone mass, muscle mass, and strength. 

As for how the gel actually works, it reduces sperm count to a threshold that is considered effective for contraception, per senior researcher and chief of the Contraceptive Development Program at the NIH, Diana Blithe (via Endocrine Society). That is one million or less sperm per milliliter of semen. Although the contraceptive method is still a long way away from hitting pharmacies, researchers behind Nestorone/Testosterone gel are hopeful because this is the furthest a male hormonal contraceptive method has gotten. The team has been formulating the gel since 2005 and testing it since 2009. Results of the phase 2 clinical trial showed that out of 222 men who took part in the study, 86% reached the reduced sperm count threshold by week 15. Others got there faster (4-8 weeks). Now for the all-important topic — side effects. 

What are the side effects of Nestorone/Testosterone gel?

Participants of clinical trials have reported back acne and weight gain as possible side effects from the gel. Thirty-five-year-old Matthew Treviño from Sacramento, California told UNFOLD, a podcast by UC Davis, that he experienced a heightened sex drive. 

Mood swings were another concern, although not to the same extent as with female hormonal birth control pills, per Diana Blithe (CNN). "I would say that there's a small percentage who have mood swings that they don't like, but that's it's a relatively small number. And we've actually been surprised at how few," explained the senior researcher. The hormonal contraceptive for men was thought to be well tolerated with no serious side effects. Additionally, the men who used the gel for the study were reported to have regained their normal sperm cell count after 2-3 months of stopping its use. 

Even so, it's probably hard to narrow down all the side effects until Nestorone/Testosterone gel has reached its final stage of trials. However, at this stage, it is a promising alternative to the only existing effective male contraceptive methods out there — condoms and vasectomy. Compared to condoms, which aren't always used perfectly and have a high failure rate, and vasectomies, which are challenging to reverse, this contraceptive gel for men could prove to be a more efficient, effective, and easy way to prevent pregnancies. Speaking of contraception for men, a birth control pill for men could also be on the horizon.