A doctor with the United Nations Children's Fund has called for expanding AIDS prevention and treatment for women beyond their pregnancies.

UNICEF's Chew Luo told an International AIDS conference Wednesday in Washington that most countries do not automatically continue anti-AIDS drugs for HIV-infected women after their babies are born.

She also said girls 10 to 18 years old are often ignored by global HIV testing, prevention and treatment programs.

On Tuesday at the conference, U.S. scientists announced a new research initiative designed to help women protect themselves against HIV, the virus that causes AIDS.

The National Institutes of Health said thousands of women in Africa will be able to volunteer for a study on the use of a vaginal ring coated with an anti-AIDS drug. NIH researchers said the new ring would have to be inserted only once a month unlike previous prevention treatments — which required the ring to be applied before intercourse.

The United Nations says 34 million people live with HIV-AIDS, and 1.7 million died from the disease in 2011.