HIV/AIDS Program
Condom Update 1999
A condom is a protective barrier that fits over the penis or inside the vagina or rectum. It is made of latex, plastic or animal tissue. It catches semen and pre-ejaculate (pre-cum) before, during, and after a man ejaculates ("comes"). Condoms made from animal tissue such as lambskin are not recommended for use for protection from sexually transmitted diseases (STDs).1
When used correctly and consistently, plastic and latex condoms are protective against most sexually transmitted diseases. Sexually transmitted diseases (STDs) such as HIV, gonorrhea, chlamydia, and trichomoniasis are spread via semen and vaginal fluids. Latex and plastic condoms form a barrier between the urethra/semen and the cervix/vagina or the anal canal, thereby preventing transmission of these STDs.
Genital herpes, genital warts, chancroid, and syphilis are sexually transmitted diseases that are characterized by lesions (sores or warts) in the genital and pelvic area which produce viral or bacterial particles that can cause infection. In the case of genital herpes and genital warts, virus is often also shed from the skin when no wart or lesion is visible. Skin or mucous membrane that are not covered by a condom may still shed virus or bacteria and cause transmission.
Condoms used consistently and correctly also prevent unintended pregnancy by preventing sperm from entering the vagina. Some other methods of contraception, such as the birth control pill, Depo Provera ("the shot") Norplant, IUD, vasectomy, and tubal ligation are more effectiveat preventing pregnancy than condoms.2 Additionally, emergency contraception pills and the IUD are the only methods of birth control that prevent pregnancy after unprotected intercourse. However, condoms are the only contraceptive method that also provides protection against transmission of communicable diseases (e.g., HIV and gonorrhea). To best prevent unintended pregnancy and STD transmission, both a condom and a highly effective contraceptive should be used.
No method of contraception or disease prevention is effective when practiced incorrectly or inconsistently. Condoms, like other risk-reduction and contraceptive methods, work very, very well when used by committed individuals and couples.
Condoms help prevent STDs and unwanted pregnancies and studies show that increasing availability of condoms through community campaigns and school availability programs does not increase sexual activity in targeted populations.4,5
Latex condoms are made from the milky sap from rubber trees, a strong material that does not allow passage of sperm, bacteria, or viruses including HIV.6
Latex condom effectiveness
Sexually Transmitted Disease Prevention: Latex condoms, when used consistently and correctly, are highly effective and reliable in reducing the risk of transmitting and acquiring HIV and other sexually transmitted diseases through sexual intercourse.7,8,9,10
Laboratory studies show that latex condoms are 98% effective in preventing STDs (including HIV) from crossing the mechanical barrier of the condom. However, the actual effectiveness of condoms during sexual activity is more difficult to assess; often, it is difficult to determine if a user has been exposed to an infected partner or whether the condom was correctly used. However, several cross-sectional and case-control studies show that latex condoms users and/or their partners have lower frequency of gonorrhea, pelvic inflammatory disease, and cervical cancer than people who do not use condoms.11 Other studies show that when condom use is increased, STD rates (including HIV) are reduced.12,13
HIV Prevention: Results from several recent studies confirm that latex condoms substantially reduce the risk of HIV transmission between sexual partners when used consistently and correctly. In a two-year study in Europe among couples in which one partner was infected with HIV and the other uninfected (HIV sero-discordant couples), researchers demonstrated that consistent use of condoms reduced significantly the chance of passing HIV from the infected partner to the one not infected. Among 124 discordant couples who used condoms consistently over the study period, none of the uninfected partners became infected with HIV. In contrast, among 121 discordant couples who did not use condoms consistently, 12 (10%) of the uninfected partners became infected during the study period.14 Other researchers concluded that the per contact probability of transmission of HIV was reduced 90-95% by the use of condoms.15
Researchers point out that condoms are not 100% effective, noting that even the correct use of condoms, especially in very high-risk situations, will result in a few new infections with HIV. Nonetheless, among sexually active people, HIV transmission is minimized by the correct and consistent use of latex condoms. Clearly, when condom use is increased, rates of HIV (and STDs) are reduced.16,17 Even when used inconsistently condoms can significantly reduce the transmission of HIV infection.18
Pregnancy prevention: The contraceptive effectiveness rate of latex condoms varies from 87% to 98%, depending on the study population and (most importantly) consistency of use.19 If used correctly for every act of intercourse, latex condoms are 98% effective at preventing pregnancy. However, when user error (such as not putting the condom on correctly) is included, condoms have a contraceptive effectiveness closer to 87%.
Latex condoms for anal sex: There is no doubt that the use of latex condoms for anal intercourse helps reduce the risk of transmission of STDs, including HIV.20 However, there are very few studies that have actually looked at the efficacy of condoms during anal sex. A review of this subject, published in 1997, states that the few studies that have been done show varying rates of condom breakage and slippage and that these rates are higher on average than rates for vaginal intercourse.21 Because of the higher risk of transmission of HIV through anal intercourse, condom breakage during anal intercourse could have very serious consequences. Nonetheless, several studies document that in high risk sexual situations, consistent condom use significantly reduces but does not eliminate new infections with HIV.22, 23
Latex condom breakage rates: New studies show that latex condom breakage rates are very low, that latex condoms have few defects, and that latex condoms are good barriersto infectious diseases. Latex condoms do not have naturally occurring holes or pores that allow infectious particles to pass through.24 A prospective study on the prevalence of condom breakage and slippage showed that among 353 instances of intercourse among Nevada prostitutes and their clients, there were no reports of broken condoms, and there were only two reports of condoms slipping off during withdrawal.25 Another study reported a breakage rate of 2.1% and slippage rate of 1.1% for latex condoms during intercourse.26 In a French study of over 700 heterosexuals, the condom breakage rate was 3.4%, and the slippage rate was 1.1%.27
Maximizing latex condoms effectiveness: Studies have also shown that personal experience in using latex condoms decreases their breakage rate.28, 29, 30, 31, 32, 33 External lubrication of latex condoms (with water-based lubricants only) has also been shown to decrease the breakage rate without significantly increasing the slippage rate.34 Use of both an internal and external condom for the same act of intercourse is not recommended due to the possibility of friction increasing the chance of condom failure.35
To ensure maximum condom effectiveness and minimize failure:
- Use water-based lubricant with latex condoms.
- Do not use oil-based lubricants with latex condoms.
- Store latex condoms in a cool, dry place.
- Do not store latex condoms in direct heat or sunlight.
- Use undamaged condoms before the expiration date on the package.
- Do not use condoms in damaged packages or showing obvious signs of age.
- Practice using latex condoms before using them with a partner.
Plastic condoms are made from polyurethane, a strong material that does not allow passage of sperm, bacteria, or viruses including HIV.36 Polyurethane has good heat transfer characteristics, is less susceptible than latex to deterioration during storage and with oil-based lubricants, and causes fewer allergies.37 Two kinds of plastic condoms are now available. The male or "external condom" (Avanti) has the same shape and is used in the same way as the latex condom. The female or "internal condom" (Reality) is a long, wide tube with one open end and one closed end. The closed end is inserted into the vagina or anus with the help of a plastic ring within the condom. The sheath adheres to the vaginal/rectal wall, fitting on the wall like a second skin. The open end also has a plastic ring and hangs outside the vagina or anus, forming the external opening of the plastic sheath. The outer ring and about an inch of the sheath remain outside the body and provide some protection to the area near the opening of the vagina or anus.
Sexually Transmitted Disease and HIV Prevention: A recent laboratory study shows that under severe test conditions, polyurethane and latex condoms are substantial barriers to virus and bacteria transmission. Polyurethane condoms yielded results not statistically different from those for latex condoms.38 Other studies show that consumers express satisfaction with Avanti condoms. Because it has been shown that the external plastic condoms create good protection from virus and bacteria particles and because people indicate that they are able and willing to use the external plastic condoms, external plastic condoms probably reduce the transmission of sexually transmitted diseases including HIV. The effectiveness rates of STD and HIV prevention for polyurethane condoms in actual use have not been established. Studies are currently underway.
Pregnancy prevention: As discussed above, studies indicate that the polyurethane male condom provides a good barrier to passage of sperm into the vagina and that consumers are satisfied with the comfort and use of the plastic condom. Although we predict that the external polyurethane condom reduces risk of unwanted pregnancy, the contraceptive effectiveness rates of polyurethane condoms in actual use have not been established. Studies are currently underway.
External plastic condom for anal sex: As discussed above, studies indicate that the polyurethane male condom provides a good barrier to prevent exposure to HIV and that consumers are satisfied with the comfort and use of the plastic condom. Again, although we predict that the external polyurethane condom reduces the transmission of HIV and other STDs during anal sex, the effectiveness rates for polyurethane condoms during anal sex have not been established.
External plastic condom bnreakage rates: A recent review of preliminary studies examining male polyurethane condoms found no significant differences in slippage and breakage rates between latex and polyurethane condoms and concludes that they perform at least as well as latex condoms.38 However, some study results as well as anecdotal reports suggest that the thinner version of Avanti condoms (available initially but now off the market) broke at a higher rate than latex condoms.39,40 The Avanti condoms now being distributed are thicker (although some of the thinner ones may remain on store shelves).
Maximizing external plastic condom effectiveness: Use of both an internal and external condom for the same act of intercourse is not recommended due to the possibility of friction increasing the chance of condom failure.41
To ensure maximum condom effectiveness and minimize failure:
- Use lubricant (either oil or water based) with external plastic condoms.
- Practice using the external plastic condom before using it with a partner.
- Store condoms in a cool, dry place.
- Use undamaged condoms before the expiration date on the package.
- Do NOT use condoms in damaged packages or showing obvious signs of age.
Reality internal plastic condom effectiveness: Use of
Reality internal plastic condom effectiveness
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Sexually Transmitted Disease and HIV Prevention: In vitro studies (studies conducted using test tubes in a laboratory) have shown that Reality, the female condom, provides an effective barrier to passage of microorganisms including HIV. Passage of organisms smaller than hepatitis B (the smallest virus known to cause an STD) and one-fourth the size of HIV, was blocked by the female condom.42, 43 Calculations, based on correct and consistent use, estimate a 97.1% reduction in the risk of HIV infection for each act of intercourse with correct use of the female condom.
Studies in numerous countries and many different cultures show that 50% to 70% of male and female participants found the female condom to be acceptable. Couples reported that use of the female condom did not interfere with a sensitive and pleasurable sexual relationship. Preliminary results of a large study including more than 1600 low-income, minority, at-risk women in Philadelphia demonstrated that, when offered a variety of preventive options, 87% chose the female condom. The study also showed that availability of the female condom resulted in an overall reduction in the number of unprotected acts of intercourse.44
The study of STD reinfection rates in 104 sexually active women with documented trichomonas and chlamydia infection demonstrated that none of the 54 participants who consistently used the female condom were reinfected. Non-compliant users and the control group had trichomonas reinfection rates of 14.7% and 14%, respectively. Three non-compliant users were reinfected with chlamydia.45
Recent results of a controlled study of STD transmission in female sex workers in Thailand showed that when both the female and male condoms were available, there was a 34 percent decrease in the rate of sexually transmitted diseases and a 25 percent decrease in the number of unprotected sex acts compared with the STD transmission rate in a similar group with access solely to the male condom.46 These findings suggest that when the female condom is available, it provides an additional measure of protection against STD transmission and HIV infection.
Pregnancy prevention: In one study of female condom use in 221 women, the pregnancy rate after 6 months was 2.6% with correct and consistent use. The failure rate was 12.4% with inconsistent or incorrect use (typical use.)47 A similar United Kingdom study of 110 women demonstrated a 12-month pregnancy rate of 5% with correct and consistent use. The failure rate for typical use was 15%.48
The pregnancy rate for the female condom during "typical use" (including incorrect and inconsistent use) was determined to be approximately 26% per year, as compared to a 15% failure rate with the male latex condom. With perfect use—use with each act of intercourse—the female condom has a failure rate of only 5%, compared to 3% for the male latex condom.49
Internal plastic condom for anal sex: Although Reality was originally manufactured for vaginal use, it is also being used by men and/or women for anal intercourse. There are limited data regarding slippage rates for anal sex and even less data on slippage rates for anal use when the inner ring is removed.
Studies indicate that the internal plastic condom provides a good barrier to prevent exposure to HIV and other STDs and that consumers are satisfied with the comfort and use of the internal plastic condom. Although we predict that the internal plastic condom reduces the transmission of HIV and other STDs during anal sex, the effectiveness rates for internal plastic condoms during anal sex have not been established.
Internal plastic condom breakage rates: An in vivo reliability study, comparing male and female condoms established that the breakage rate during use for the female condom was much lower that the breakage rate for the male condom.
In limited studies on the effectiveness of the internal plastic condom, results show that when used consistently the breakage rate was comparable to latex condoms.50, 51
Maximizing internal plastic condom effectiveness: A variety of studies show that women find insertion of the internal plastic condom easier with repeated use. Unpublished data indicate that women can increase their successful use of the internal condom with training on (1)how to insert it and (2)how to assure that the penis is not inserted outside of the condom.
Use of both an internal and external condom for the same act of intercourse is not recommended due to the possibility of friction increasing the chance of condom failure.52
To ensure maximum condom effectiveness and minimize failure:
- Use enough lubricant (either water or oil based) so that the condom stays in place during sex.
- Gently guide the penis into the sheath's opening with your hand, to ensure that it enters properly. Be sure that the penis is not entering to the side of the sheath.
- Use undamaged condoms before the expiration date on the package.
- Do NOT use condoms in damaged packages or showing obvious signs of age.
- Practice putting the internal condom in place before using it with a partner.
Advantages of condom types
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Latex condoms:
- They have been studied extensively.
- They are widely available.
- They are relatively cheap.
- People have more experience using them.
Internal plastic condoms:
- The person using them (the receptive partner) can control the safety of intercourse.
- Users can insert them well before intercourse takes place.
- Plastic causes fewer allergic reactions than latex.
- Can be used with oil based and water based lubricants.
- Provides broader coverage than the male condom, covering the labia, the peri-anal region and the base of the penis.
External plastic condoms:
- Plastic causes fewer allergic reactions than latex.
- Can be used with oil based and water based lubricants.
Disdvantages of condom types
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