Condoms are barrier methods of contraception. They help prevent pregnancy by stopping sperm meeting an egg. They also help protect you from sexually transmitted infections.
An external condom fits over an erect penis. It’s made of very thin latex (rubber), polyurethane (soft plastic) or polyisoprene. It’s sometimes called a male condom. An internal condom is put in the vagina and loosely lines it. It’s made of polyurethane or nitrile polymer (synthetic rubber). It’s sometimes called a female condom.
Effectiveness of condoms
When used consistently and correctly, latex condoms are highly effective in preventing the sexual transmission of HIV (during vaginal, oral, or anal intercourse). Latex condoms are also effective in preventing pregnancy and several sexually transmitted infections (STIs). Using condoms lowers women’s risk of developing cervical cancer, a disease associated with HPV. Consistent use of condoms can also help people clear HPV infection and/or reduce their risk of re-infection.
If 100 sexually active women don’t use any contraception, 80 to 90 will become pregnant in one year.
External condoms – If always used correctly, according to instructions, they’re 98% effective at preventing pregnancy. This means that 2 in 100 women will get pregnant in one year. If they’re not always used correctly, about 18 in 100 women will get pregnant in one year.
Internal condoms – If always used correctly, according to instructions, they’re 95% effective at preventing pregnancy. This means that 5 in 100 women will get pregnant in one year. If they’re not always used correctly, about 21 in 100 women will get pregnant in one year.
Condoms Are Highly Effective in Preventing HIV Infection.
Sexual transmission of HIV occurs when infected semen, vaginal, or other body fluids contact mucosal surfaces, such as the male urethra, the vagina, or cervix. According to the Centers for Disease Control and Prevention (CDC), a number of carefully conducted studies, employing rigorous methods and measures, have demonstrated that consistent condom use is highly effective in preventing HIV transmission.
In a two-year study of sero-discordant couples (in which one partner was HIV-positive and one was HIV-negative), no uninfected partner became infected among couples using condoms correctly and consistently at every act of vaginal or anal sex versus 10 percent of those using condoms inconsistently. (de Vincenzi I)
In a similar two-year study, two percent of uninfected partners who used condoms consistently became HIV-infected versus 12 percent among those who used condoms inconsistently or not at all. (CDC)
A recent study of declining HIV prevalence in Uganda found no evidence that abstinence or monogamy had contributed to the decline. Findings identified the increased use of condoms in casual relationships as important in Uganda’s declining HIV infection rates. (Wawer MJ et al.)
Gonorrhea, chlamydia, and trichomoniasis are transmitted when infected semen or vaginal fluids contact mucosal surfaces. Because condoms block the discharge of semen or protect the male urethra against exposure to vaginal secretions, condoms provide a greater level of protection against these STIs. (CDC)
Condoms also provide some protection against genital ulcer STIs—such as genital herpes, syphilis, and chancroid—which are transmitted through contact with mucosal surfaces or infected skin. Because these STIs may be transmitted across surfaces not covered or protected by the condom, condoms provide a lesser degree of protection against them. (Holmes KK et al.)
Condoms Are Effective in Reducing Risk for HPV and Cervical Cancer.
Almost all cases of cervical cancer are caused by HPV. While at least 3.1 million women in the United States are newly infected each year with HPV, perhaps as many as 40,000 develop non-invasive cervical cancer and less than 11,000 develop invasive cervical cancer. (American Cancer Society 2004)
Regular Pap smears can detect precancerous conditions long before cervical cancer develops orbecomes invasive, permitting women and their doctors to prevent cervical cancer. (American Cancer Society 2004)
In a 28-month study of 123 college women, researchers found that sexually active women who used condoms consistently were significantly less likely to contract HPV than were women who had not used condoms. (Winer RL et al)
In a study among 148 women already diagnosed with a pre-cancerous cervical condition and their male partners, 53 percent of women who used condoms had normal cervical findings at two consecutive follow-ups, versus 35 percent of women who did not use condoms.
In the same study, 23 percent of women who used condoms cleared HPV from their system (as shown by HPV testing) compared to four percent of women who did not use condoms. (Hogewoning CJA et al) In one study, men who used condoms consistently and correctly had reduced risk for penile infection with HPV.
Another study showed that men who consistently used condoms had a lower incidence of anal HPV infection than did inconsistent or non-users. In one study, men who consistently used condoms showed a faster regression in penile HPV lesions than did men who did not use condoms (Chin-Hong PV et al)
• Use a new condom for every act of vaginal, anal and oral sex—throughout the entire sex act (from start to finish). Before any genital contact, put the condom on the tip of the erect penis with the rolled side out.
• If the condom does not have a reservoir tip, pinch the tip enough to leave a half-inch space for semen to collect. Holding the tip, unroll the condom all the way to the base of the erect penis.
• After ejaculation and before the penis gets soft, grip the rim of the condom and carefully withdraw. Then gently pull the condom off the penis, making sure that semen doesn’t spill out.
• Wrap the condom in a tissue and throw it in the trash where others won’t handle it.
• If you feel the condom break at any point during sexual activity, stop immediately, withdraw, remove the broken condom, and put on a new condom.
• Ensure that adequate lubrication is used during vaginal and anal sex, which might require water-based lubricants. Oil-based lubricants (e.g., petroleum jelly, shortening, mineral oil, massage oils, body lotions, and cooking oil) should not be used because they can weaken latex, causing breakage.
Sperm can get into the vagina during sex, even if you use a condom. This may happen if:
• The penis touches the area around the vagina before a condom is put on (pre-ejaculation fluid (pre-cum), which leaks out of the penis before ejaculation, may contain sperm)
• The condom splits
• The condom doesn’t fit properly
• The external condom is put on inside-out
• You don’t use the condom according to instructions
• The external condom slips off the penis
• The internal condom gets pushed into the vagina
• The penis enters the vagina outside of an internal condom
• The condom gets damaged, for example by sharp fingernails or jewellery
• You use too much or too little lubricant
• You use oil-based products (such as body lotions) with latex condoms; these can damage the condom. If any of these happen, or if you’ve had sex without using contraception, you can get advice about emergency contraception.