"Teenagers from time immemorial have been sexually active and we need as a society to help protect them," Beilenson said.
At least 50 percent of sexually active men and women have an HPV infection at some point in their lives, and much of it clears up on its own. Most people with HPV do not develop symptoms or health problems. But sometimes, certain types of HPV can cause genital warts in men and women while other HPV types can cause cervical or other cancers.
The CDC recommends that girls and women ages 11 to 26 be vaccinated against HPV.
The CDC also recommends annual chlamydia screening for sexually active women under the age of 25. The symptoms are often silent, and women might not know they have it. But left untreated, it can cause irreversible damage, particularly to fertility.
There are misperceptions about who is at risk - both among teens and health care providers, Douglas said. And there remains a taboo in many circles about discussing these infections.
Erbelding, at Bayview, said the results of the study should remind doctors and parents that girls as young as middle school age need to be prepared for all that comes with becoming sexually active.
"If their kids are going to be armed with the tools to protect themselves from pregnancy and STDs, the discussion needs to start before age 14," she said.
stephanie.desmon@baltsun.com
