At least one in four teenage girls nationwide has a sexually transmitted disease, or more than 3 million teens, according to the first study of its kind in this age group.
A virus that causes cervical cancer is by far the most common sexually transmitted infection in teen girls aged 14 to 19, while the highest overall prevalence is among black girls—nearly half the blacks studied had at least one STD. That rate compared with 20 percent among both whites and Mexican-American teens, the study from the federal Centers for Disease Control and Prevention found.
About half of the girls acknowledged ever having sex; among them, the rate was 40 percent. While some teens define sex as only intercourse, other types of intimate behavior including oral sex can spread some infections.
The study by CDC researcher Dr. Sara Forhan is an analysis of nationally representative data on 838 girls who participated in a 2003-04 government health survey. Teens were tested for four infections: human papillomavirus, or HPV, which can cause cervical cancer and affected 18 percent of girls studied; chlamydia, which affected 4 percent; trichomoniasis, 2.5 percent; and herpes simplex virus, 2 percent.
Blythe said the results are similar to previous studies examining rates of those diseases individually.
The results were prepared for release Tuesday at a CDC conference in Chicago on preventing sexually transmitted diseases.