STEVE INSKEEP, HOST:
And we have news this morning about another form of contraception. Nonoxynol-9, or N9, is found in many over-the-counter contraceptives. It was once thought to protect against HIV, but we now know it can actually increase a person's HIV risk. People who use it may not be fully informed.
Some listeners may find the contents of this report - lasting about four minutes - uncomfortable. Here's Gretchen Cuda-Kroen.
GRETCHEN CUDA KROEN, BYLINE: When Lisa Rentz decided she'd had enough of birth control pills, she walked into her local drug store and picked up something different: a vaginal contraceptive film that contains the spermicide N9. Rentz admits she didn't read the instructions all that closely, but simply assumed any over-the-counter product was safe.
LISA RENTZ: I was not aware of the increased chances of HIV transmission - which is alarming. I mean, that does seem to me to be something that should be printed larger on the box.
KROEN: Dozens of condoms, vaginal films, jellies, foams and sponges containing N9 are available online, or from your local pharmacy, without a prescription. Experts say they're perfectly safe, as long as they're used as directed - not used more than once a day; and not used for anal intercourse, with multiple partners, or with a partner who has HIV or other STDs.
Michael Rosenberg is a former researcher at the Centers for Disease Control and Prevention.
MICHAEL ROSENBERG: One of the risks that everybody who uses spermicide should be aware of is that if there is a likelihood that your partner may have one of these sexually transmitted diseases, then it should probably be used with caution. So a product like this is probably best used with a couple who's monogamous.
KROEN: Ironically, Rosenberg says N9 is actually very effective at killing the microorganisms that cause STDs, like chlamydia, gonorrhea and HIV. There's just one, small problem - it also irritates the lining of the vagina and the rectum, making them more vulnerable to attack by those same viruses and bacteria.
ROSENBERG: Well, nonoxynol-9 is a detergent, and what that means is that it disrupts the layers of the cell membranes. So theoretically, at least, it could protect against things like chlamydia and gonorrhea and HIV. The thing is that it also dissolves mammalian cells. So when you use it a lot, it can actually erode a lot of the cells that are present, that help protect against these diseases.
KROEN: It's easy to wonder why products containing N9 are still available at all. One reason is that less than 1 percent of U.S. women use spermicides, and experts say most of them are unlikely to have an HIV-infected partner. It's also because barrier birth- control methods, like the diaphragm or cervical cap, must be used with a spermicide. And pulling N9 off the market – it's the only spermicide available in the U.S. - would effectively eliminate those few existing non-hormonal sources of birth control.
Mayo Clinic OB-GYN Petra Casey says that for some women - women like Rentz, who've been in a monogamous relationship for years with an HIV-negative partner - there is virtually no risk at all. Women simply need to be well informed so they can choose a birth control method that's right for them.
DR. PETRA CASEY: Those that don't go to their health-care provider, and just obtain these over-the-ounter products may or may not read the package labeling from top to bottom, so they may not be as aware. But we are looking at a fairly small group of women, plus we are looking at a fairly low-risk population in most situations. So it's not, certainly, a huge public-health problem, in my view.
KROEN: Another factor, says Rosenberg, is that the studies that demonstrated an increased risk for HIV were done with prostitutes, who used the products multiple times a day. And it's thought the risk is lower for women who use spermicides less frequently.
ROSENBERG: If you use these a couple of times a week, I suspect that you're fine. And I think if there is any increased risk at all, it's very minimal - and it might even be protective. It's hard to know in these populations because they haven't been studied.
KROEN: But for high-frequency users - women at high risk for HIV, or those with HIV-infected partners - experts say a condom is a much better choice.
For NPR News, I'm Gretchen Cuda Kroen.
INSKEEP: And that's "Your Health" for this Monday morning. I want to mention that you can follow MORNING EDITION on Facebook as well as on Twitter. On Twitter, we are @morningedition and @NPRInskeep.
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