Sex during adolescence doesn’t predict future HPV infection
An adolescent’s sexual behavior — or lack thereof — should not determine whether or not she gets vaccinated against the human papillomavirus to protect against future HPV infection, say researchers at the C.S. Mott Children's Hospital’s Child Health Evaluation and Research (CHEAR) Unit.
The study, set to appear in the July issue of the journal Pediatrics, finds women who were sexually active as adolescents were just as likely as women who were not sexually active during their youth to get HPV as adults.
“Using risk factors as a means to determine who should get the HPV vaccine is not a good strategy. In our study, all women who eventually became sexually active at some point had an equivalent risk of getting HPV,” says study lead author Dr. Amanda Dempsey, a member of the CHEAR Unit in the Division of General Pediatrics.
These findings, Dempsey says, support the Centers for Disease Control and Prevention’s Advisory Committee on Immunizations Practices (ACIP) recommendation for universal vaccination for all women ages 11-26, regardless of sexual experience.
Much of the confusion over whether or not to vaccinate a patient stems from conflicting recommendations. While the ACIP advocates for universal vaccination, the American Cancer Society recommends vaccinating all females younger than 18, and selectively vaccinating women ages 19 to 26 based on an informed discussion between the patient and her doctor about sexual history.
The price of the vaccine also is a factor. With each dose costing approximately $120 — along with high up-front costs to stock the vaccine, inconsistent coverage from government programs and low levels of reimbursement from private insurance — many states are struggling to provide the vaccine to all eligible girls and women.
For those reasons, many clinicians are targeting the HPV catch-up vaccination to girls and women they deem to be at the greatest risk for acquiring HPV. Previous studies of sexually active adolescents and young adults identified specific sexual partnerships, behavioral and sociodemographic characteristics associated with increased risk for HPV infection.
The problem, Dempsey says, is that those studies only looked at women currently infected with HPV, and retrospectively analyzed potential risk factors for infection.
Estimates suggest that more than 80 percent of the U.S. population will have had an HPV infection by the time they reach the age of 50.
HPV infection generally occurs shortly after a woman becomes sexually active. Most women never know they have the virus because it usually goes away on its own and may not cause any symptoms. There are more than 100 types of HPV, but only some types of HPV lead to cervical cancer or genital warts. The vaccine guards against four types of HPV: two that cause 70 out of 100 cases of cervical cancer and two that cause 90 out of 100 cases of genital warts.
Achamyeleh Gebremariam, with the CHEAR Unit in the Department of Pediatrics at the U-M Health System, was a coauthor for the report.