March 11, 2008 -- One in four teenage girls in the United States is infected with a sexually transmitted disease, according to data released Tuesday by the CDC.
The figures, based on research conducted in 2003 and 2004, show that nearly one in five girls between 14 and 19 years old is infected with human papillomavirus (HPV), which can cause of cervical cancer and genital warts. About one in 25 girls carries chlamydia, a sexually transmitted bacterium.
"What we found is alarming," says Sara Forhan, MD, a CDC researcher who conducted the study among 838 girls nationwide.
"These numbers translate into 3.2 million young women aged 14 to 19 who are infected with an STD," Forhan says.
The study also showed that nearly half of adolescent African-American girls are infected with an STD. Researchers say poorer access to testing for sexually transmitted diseases contributed to the increased STD incidence in that group.
"This does not mean that African-Americans are taking greater risks individually," says John Douglas Jr., MD, director of the CDC's division of STD prevention.
Screening Falling Short
The CDC recommends regular chlamydia screening at least yearly for all sexually active women and for females 25 years old and younger. All pregnant women should also be screened because the infection can pass to the baby during delivery. But only about one-third of females get proper screening, Douglas says.
Experts recommend regular screening primarily because most women with chlamydia infections don't have noticeable symptoms. That means women can carry the infectious for years without knowing they have it, putting them at risk for pelvic inflammatory disease and infertility.
The CDC also recommends HPV vaccination for all women and girls between 11 and 26. The vaccine comes in three doses and covers four strains of the virus.
Still, Douglas says STD testing is rife with "missed opportunities." Another study unveiled by the CDC showed that only 40% of female patients who go to a doctor for emergency contraception, such as the "morning after pill," also receive advice and testing for STDs.
Both studies were presented at the National STD Prevention Conference in Chicago.
"An emergency contraception prescription is a missed opportunity because by definition that was unprotected sex," Elizabeth Alderman, MD, director of adolescent medicine at Children's Hospital at Montefiore in New York, tells WebMD.
Alderman says many clinics don't have easier-to-use urine-based testing for chlamydia.
Douglas says abstinence is "the surest way to prevent getting an STD." The agency also pushes monogamous sexual relationships and the consistent use of condoms, he says.
Alderman says the majority of sexually active teens in her practice use condoms. If you ask, "some of the time, all the time, or most of the time,' you'll usually get a "most of the time," she says.