CHICAGO — Shots that protect against cervical cancer do not make girls promiscuous, according to the first study to compare medical records for vaccinated and unvaccinated girls.
The researchers did not ask girls about having sex, but instead looked at ‘‘markers’’ of sexual activity after vaccination against the sexually transmitted human papillomavirus, or HPV. Specifically, they examined up to three years of records on whether girls had sought birth control advice; tests for sexually transmitted diseases or pregnancy; or had become pregnant.
Very few of the girls who got the shots at age 11 or 12 had done any of those over the next three years, or by the time they were 14 or 15. Moreover, the study found no difference in rates of those markers compared with unvaccinated girls.
The study involved nearly 1,400 girls enrolled in a Kaiser Permanente health plan in Atlanta. Results were published online Monday in Pediatrics.
Whether vaccination has any influence on similar markers of sexual activity in older teens was not examined in this study but other research has suggested it does not.
The study is the first to use medical outcomes data to examine consequences of HPV vaccination and the results are ‘‘comforting and reassuring,’’ said lead author Robert Bednarczyk, a researcher at Kaiser and Emory University. Both institutions paid for the study.
HPV is the leading cause of cervical cancer and also has been linked with anal and oral cancers in women and men.
The federal Centers for Disease Control and Prevention and the American Academy of Pediatrics recommend HPV shots for girls and boys at age 11 or 12, before they have ever had sex.
Some parents have raised concerns that the shots ‘‘are a license to have sex,’’ but the study bolsters evidence against that concern, said Dr. Elizabeth Alderman, at The Children’s Hospital at Montefiore in New York City.