Female condoms, also called internal condoms, do prevent STDs. With perfect use, they are about 95% effective at blocking HIV and other sexually transmitted infections. With typical use, that number drops to around 79%, largely due to inconsistent use or insertion errors. Like external (male) condoms, they work as a physical barrier that stops infectious fluids from passing between partners, and the materials used are impermeable to even small virus particles.
Which STDs They Protect Against
Internal condoms are most effective against STDs that spread through genital fluids. This includes gonorrhea, chlamydia, and HIV. The nitrile material used in the current FDA-approved model (FC2) has pore sizes small enough to block even the smallest viruses, making it a reliable barrier for fluid-borne infections.
Protection is more limited for STDs that spread through skin-to-skin contact, such as genital herpes, HPV, and syphilis. The internal condom does cover more of the external genital area than a male condom, since its outer ring sits outside the vaginal opening. But it still can’t cover every area where skin contact occurs, so transmission of these infections remains possible even with correct use.
How They Compare to Male Condoms
A study of women at high risk for STDs found that the two types of condoms fail in different ways. Female condoms broke far less often, at a rate of just 0.1% compared to 3.1% for male condoms. However, female condoms slipped more frequently: 5.6% of the time versus 1.1% for male condoms.
Experience matters significantly with both types. For female condoms, the combined failure rate (breakage plus slippage) dropped from 20% on first use all the way down to 1.2% after 15 or more uses. Male condoms showed a similar learning curve, falling from 9% to 2.3%. So if female condoms feel awkward at first, that’s normal, and performance improves quickly with practice.
A systematic review published in BMC Public Health found that using female condoms alongside male condoms may be as effective as male condoms alone for preventing HIV, and potentially more effective at preventing other STIs. That said, you should never use both at the same time during a single act of sex. The friction between the two condoms increases the chance that one or both will fail.
How to Use One Correctly
Correct use is the biggest factor in whether an internal condom actually protects you. The CDC recommends these steps:
- Before sex: Open the package carefully to avoid tearing the condom. The thick inner ring with the closed end goes inside the vagina. The thinner outer ring stays outside, covering the vaginal opening.
- Inserting: Find a comfortable position. Squeeze the sides of the inner ring together and insert it into the vagina, then push it up with your finger until it rests against the cervix. Make sure the condom isn’t twisted.
- During sex: Guide your partner’s penis into the condom’s opening. If the condom gets pushed inside or the outer ring slips in, stop and reposition it.
- After sex: Twist the outer ring gently to keep fluids contained, then pull the condom out. Throw it away. Never reuse it.
The condom comes pre-lubricated on both sides. If you want additional lubricant, use water-based or silicone-based products. Oil-based lubricants can damage the condom material and compromise the barrier.
Why Some People Prefer Them
Internal condoms give the receptive partner direct control over protection, which can be important when negotiating condom use is difficult. They can be inserted up to eight hours before sex, so they don’t interrupt the moment the way external condoms sometimes do. They’re also a good option for people with latex allergies, since the FC2 is made from nitrile rather than latex. And because they’re worn internally, they don’t require the penetrating partner to maintain an erection for the condom to stay in place.
Where to Get Them and What They Cost
Internal condoms are harder to find than male condoms. The only FDA-approved brand available in the U.S. is the FC2, which you can buy online through the manufacturer’s website, at many Planned Parenthood health centers, or at family planning clinics. Drugstores carry them but typically require a prescription. They cost about $2 to $3 each, usually sold in packs of 12. Some clinics and health centers provide them for free, and insurance may cover the cost if you have a prescription.
In 2018, the FDA reclassified the female condom from a Class III to a Class II medical device, putting it in the same regulatory category as the male condom. That reclassification was a recognition that internal condoms have a well-established safety and effectiveness profile, and it may eventually make them easier to access over the counter.