Researchers at Boston University discovered a way to make condoms that self-lubricate on contact — a discovery that could encourage more people to use condoms and reduce rates of unintended pregnancies and sexually transmitted infections.

The study was published Wednesday in Royal Society Open Science.

Condoms are one of the most cost-effective global health interventions. When used properly, they’re 98 percent effective at preventing pregnancy and highly effective at preventing the transmission of HIV/AIDS. UNAIDS estimates that condom use has averted 45 million HIV infections since 1990.

While unintended pregnancy rates are declining, 44 percent of pregnancies worldwide are still unintended. HIV rates are also declining, but there were still 1.8 million new HIV infections last year. About a third of American men aged 15–44 used a condom the last time they had sex. Globally, some 40 percent of men and women didn’t use a condom the last time they had sex with a non-regular partner.

So why aren’t people using them? The reasons are complex: There’s social and cultural stigma attached to condoms in many countries, other people struggle to afford them, and some people don’t use them because they’re with a monogamous partner or because they’re trying to get pregnant.

But one important reason is that people say sexual intercourse doesn’t feel as good while wearing a condom. In one study in the UK, 77 percent of men and 40 percent of women said condoms reduced pleasure. In eight sub-Saharan African countries, the number one reason for not using condoms with a casual partner was disliking them, which included the perception that they reduced pleasure. Studies in Nepal and Indonesia of female sex workers showed that male clients resisted condom use because of reduced pleasure.

Another problem with condoms is that they break. Latex acts as a great barrier, but it can also increase friction and cause condoms to rupture. Lubricants can reduce that friction and increase pleasure, but using them requires an extra step and money.

Self-lubricating condoms, on which clinical trials will start next year, could be a major breakthrough: 73 percent of people surveyed said they preferred the way the self-lubricating condoms felt and that they would be more likely to use these condoms. The study relied on a small sample size — only 33 people — but results hew to a national survey of Americans that found that 61.5 percent of women and 66.1 percent of men said lubricated sex felt better.

Another benefit is that these condoms keep their lubrication a lot longer — up to 1,000 thrusts, according to the research, which is twice as long as normal water-based lubricants.

Improving upon an ancient technology

Considering how important they are, condoms are still pretty primitive; they haven’t advanced a whole lot since the ancient Romans were using animal bladders.

“The last advance in condom technology is more than 50 years ago, and that was when silicon oil got introduced as a lubricant,” professor Mark Grinstaff, a co-author of the Boston University study, told the Guardian. “We are using our grandparents’ technology in the 21st century, which is crazy.”

In 2013, the Bill and Melinda Gates Foundation put out a call for proposals to change this, soliciting designs for condoms that preserved or enhanced pleasure. They received over 800 submissions and chose 11 projects, including the researchers from Boston University, to give $100,000 each in seed funding to start research, with the possibility of an additional $1 million.

The recipients included one project that aimed to put a modern twist on traditional lambskin condoms by using collagen fibers from bovine tendons, which they hoped would replicate the feel of human skin. Another project proposed a condom that would tighten around the penis during sex like shrink wrap, increasing pleasure. A couple of the projects proposed condoms with applicators, another that “clings like Saran Wrap rather than squeezes,” and others that warm on contact.

Five years later, most of the projects have yet to come to fruition, making the research out of Boston that much more exciting.

The man responsible for the bovine condom idea, Mark McGlothlin, president of Apex Medical Technologies, told Mic in 2015 that, for all the publicity Gates received for the project, the funding wasn’t enough to get products to market. Getting products through the Federal Drug Administration approval process can take years, if not decades — particularly with something as sensitive as condoms. As a result, a lot of the research has petered out.

Still, some of the other products remain in development. Lakshminarayanan Ragupathy of HLL Lifecare Ltd. is still developing one of the heat-sensitive condoms and also began work on developing a biodegradable condom, as most condoms take years to decompose.

Another recipient of Gates funding in Australia is working to make condoms from hydrogels, which are more “skin-like” than latex or rubber. They’re still in development, but researchers hope the product could have worldwide impact because it would “decrease the spread of disease and unwanted pregnancy without compromising sensation.”

Indeed, condoms save lives — but only when people want to use them.

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