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 nonprofit 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.