When used correctly, condoms are among the safest and most effective methods of preventing both pregnancy and sexually transmitted infection (STI). However, for condoms to be effective, there’s a major hurdle to be overcome — condoms must be worn. Most men (and some women) claim condoms reduce sensation and pleasure during sex; condom users complain that condoms smell funny, taste bad, feel constricting, and, in this age of eco-consciousness, are entirely wasteful. With this list of grievances, it is only natural (albeit more than a little disturbing) that as few as five percent of men worldwide wear condoms during sex. Even more alarmingly, according to the 2010 National Survey of Sexual Health and Behavior, only 20 percent of those in the United States who have anal sex use condoms, and anal sex is the highest risk activity for sexually transmitted infection. Fortunately, new condoms are in development that are easier to use and more pleasurable to wear.
The Platonic Form of the Condom
For a condom to be widely used,
- it has to be reliable; it shouldn’t break frequently
- It must be easy to put on, even in the heat of the moment when sexual partners fumble in the dark, sometimes while intoxicated
- It must not inhibit genital sensation so much that it ruins the sexual experience, or no one will want to wear it
- Perhaps most importantly, it must block transmission of sperm cells and smaller particles such as the bacteria and viruses that cause sexually transmitted infections.
As many of the condoms on the market demonstrate, optimizing for one property, such as sensation, tends to come at the cost of other properties, such as durability or impermeability.
The Condom of Today
Although condoms have been in use for well over a thousand years, the modern condom hasn’t changed very much over the last century. Here’s a survey of the condoms available today, and the science that supports their use.
Latex condom
The dominant condom technology currently on the market, developed in the 1920s, latex condoms and the synthetic-equivalent polyisoprene condoms are produced globally by a few large corporations that comprise an oligopoly in the sexual health market — Trojan, Durex, LifeStyles/Ansell, and Okamoto. Aside from the market pressures keeping latex dominant, there is regulatory hostility towards competing technologies as well. The FDA, Centers for Disease Control, and health departments across the country have promoted latex condoms as the gold standard of STI and pregnancy prevention for over 30 years. In many cases, the data just aren’t available to suggest that competing technologies are as safe and effective as latex condoms.
However, shockingly, in many cases the data aren’t really available to support the use of latex condoms either. Although the FDA regulates condoms as medical devices and therefore dictates how they are manufactured, labeled, and marketed, relatively few studies have actually been done on the safety and efficacy of condom use, particularly for high-risk populations such as men who have sex with men. Paradoxically, the FDA does not approve condoms for use during anal sex, and studies on condom durability are performed for vaginal sex only — despite the fact that condoms became high-profile in large part because of the HIV epidemic among men who had anal sex with other men.
“Paradoxically, the FDA does not approve condoms for use during anal sex, and studies on condom durability are performed for vaginal sex only — despite the fact that condoms became high-profile in large part because of the HIV epidemic among men who had anal sex with other men.”
Lambskin condom
Lambskin condoms, also known as natural membrane condoms, or skin condoms, are perhaps the oldest class of condoms on the market. Indeed, a history of using animal intestines as condoms dates back thousands of years. Like the sausage casings that were the lambskin condom’s forebears, lambskin condoms are thin, translucent, and stronger than they look. Because they wet easily, they are very good at transferring heat, which is perhaps the most important quality in a condom that is competent at feeling something like unprotected sex. With all these positive qualities, one might wonder why use of lambskin condoms has declined over the years. Unfortunately, the Achilles’ heel of the lambskin condom is permeability. In the wake of the AIDS crisis of the 1980s, lambskin condom use plummeted, as the FDA did not endorse lambskin condoms for the ability to prevent transmission of HIV. Recently, the tests used in the 1980s to test lambskin condoms for their permeability to HIV have been called into question, however.
An animal intestine condom from around 1900. Photo: Wikipedia
In the early studies the FDA used to set condom recommendations for HIV prevention, researchers filled condoms with a few milliliters of virus-laden solution and either pressurized the condom or allowed it to sit in saline solution for as much as 30 minutes, then tested the solution exterior to the condom for the presence of virus. In these tests, scientists erred on the side of caution rather than precisely modeling human sexual behavior. Virus concentrations were higher than those found in semen, the exposure times were longer than typical between two partners post-ejaculation, and solution volumes were higher than the typical human ejaculate volume. Interestingly, of 11 studies published on the porosity of lambskin condoms, HIV was found to leak in only one of them, and even then in only 1 of 34 condoms tested. Other studies looked at whether lambskin condoms leaked other infectious agents, but had mixed results: the condoms blocked herpes virus leakage 96 percent of the time, but did not block hepatitis B virus transmission. Based on the physical size of these virus particles, these results make sense: herpes virus and HIV are large, whereas hepatitis B virus is about half the size and can fit through lambskin condom pores.
The latex condom, however, was impervious to all infectious agent transmission — assuming the condoms didn’t break. The FDA chose to promote latex condoms rather than lambskin condoms because of impermeability of latex to smaller infectious agents, but neglected the fact that these condoms break far more often than lambskin condoms do. For the purpose of preventing spread of HIV, lambskin condoms are likely more effective than latex condoms when breakage rate is taken into account, but the FDA does not approve lambskin condoms for prevention of STIs. The scientific merit of these recommendations is somewhat questionable, but the recommendations have not changed since the 1990s. Since 1991, lambskin condoms have carried this warning: “Not to be used for prevention of sexually transmitted diseases (STDs). To help reduce the risk of catching or spreading many STDs, use only latex condoms.”
“The FDA chose to promote latex condoms rather than lambskin condoms because of impermeability of latex to smaller infectious agents, but neglected the fact that these condoms break far more often than lambskin condoms do.”
In the FDA’s vociferous advocacy for latex condom use, the lambskin condom was perhaps inappropriately branded useless, setting up a false dichotomy between using latex condoms or nothing at all. Clearly, lambskin condoms are better than nothing, yet few even consider using them for safer sex because of the FDA’s condemnation of them for the purpose of STI prevention. From a public health perspective, whether consistent use of lambskin condoms would be better than inconsistent use of latex condoms remains an open question.
Polyurethane condom
The polyurethane condom is thinner and has a better heat transfer profile than the latex condom, with comparable breakage rates of around 2 to 2.5 percent. The polyurethane condom is labeled and marketed primarily to be used as an alternative to latex condoms for people with a latex sensitivity. Although, unlike the lambskin condom, the FDA does call the polyurethane condom effective against STI transmission, the label emphasizes that the condoms are for people with latex allergies, which limits the mass-market appeal of polyurethane condoms.
Nitrile female condom
The female condom, marketed as the “FC2” condom in the United States, is a nitrile-based condom that is worn by the receptive partner during sex. Affectionately referred to as a “trash-can liner” by sex columnist Dan Savage, the FC2 condom lines the vagina or anus during sex and is intended to catch the insertive partner’s sexual fluids before they come into contact with the membranes of the receptive partner. The nitrile FC2 condom is thick and does not transfer sensation very well. However, because it is lubricated on both sides and does not constrict the penis in any way, many users of the FC2 condom report that it feels more like unprotected sex than other condoms do. However, the FC2 condom is only FDA approved for use in the vagina, and it is marketed as an alternative for women whose partners refuse to use latex condoms. Such selective marketing has arguably limited the sales of this condom overall.
The Condom of Tomorrow
Because current condoms are neither pleasurable to wear nor used as widely as would be necessary to curb the spread of HIV and other sexually transmitted diseases, there is huge opportunity to innovate in this area. Responding to this demonstrated need, a variety of funding agencies have begun to pour money into developing a better condom. For example, the Bill and Melinda Gates Foundation recently put out a call for proposals to develop what it calls the “Next Generation of Condom.”
While many of the scientists and engineers developing next-generation condoms are focused on optimizing existing well-known materials such as polyurethane, some have taken a more novel approach, working with biomaterials and newer synthetic materials.
“Unlike these thinner condoms, which attempt to transfer more sensation between sexual partners, silicone condoms focus on creating sensation for the wearer rather than transferring it”
Mark McGlothlin, president and CEO of Apex Medical Technologies, is developing one such biological, biodegradable condom. McGlothlin, who was the force behind the polyurethane condoms patented in the 1990s, is designing a condom that makes use of collagen, the main structural protein found in animal tissues also famous for producing gelatin when boiled. A condom made from highly refined collagen can grip a man’s penis like a leather glove, while conforming to the surface of the skin and allowing the heat transfer so important to sensation during intercourse.
Other condoms in development use synthetic materials that haven’t been applied in the sexual health arena previously, such as polyethylene, hydrogel, and silicone. Polyethylene and hydrogel condoms can be produced at 20 percent of the thickness of latex condoms while retaining the strength and impermeability of the older condom technology. Unlike these thinner condoms, which attempt to transfer more sensation between sexual partners, silicone condoms focus on creating sensation for the wearer rather than transferring it. The early prototype of the Origami condom, for example, is folded over the erect penis and is lubricated on the inside, allowing it to move with and stimulate the insertive sex partner. While silicone has so far been judged too bulky to use for mass production, the idea of condoms that are half sex toy, half protection is alive and well.
Summary
There is probably no such thing as a perfect condom, but it is fairly clear that whatever the perfect condom might be, the latex condom isn’t it, despite its overwhelming market dominance. Existing alternatives and the latest and greatest condom materials that science can deliver to us will pave the way for a new era of STI prevention and possibly better sex in the years ahead.
