WHAT WE KNOW: Some protection from anti-AIDS vaginal ring

Two long-awaited studies from Africa found that a vaginal ring coated with an anti-AIDS drugs once a month gave women partial protection against HIV infection. Some takeaways from the studies:

—The ring was proven safe, but worked far better in women over 25.

—Younger women got little or no protection, raising questions about whether they were using the ring properly.

—Even with the questions, the non-profit International Partnership for Microbicides says it will seek regulatory approval for wider use of the ring in parts of Africa.

—Women make up more than half of the nearly 37 million people worldwide living with HIV, most of them in hard-hit Africa.

—Aside from condoms, HIV prevention tools include taking a daily anti-AIDS pill, but this isn’t widely available in poor countries. Other attempts at HIV-blocking vaginal gels haven’t yet panned out.