Teen girls did not engage in riskier sex after HPV vaccination

Adolescent girls reported sexual behaviors that were the same or safer after the launch of a school-based routine HPV vaccination program in British Columbia, Canada, according to recently published study results in CMAJ.

“Before the introduction of the HPV vaccine, some parents expressed concern that the HPV vaccine could encourage adolescent girls to make poorer sexual choices,” Gina S. Ogilvie, MD, MSc, FCFP, DrPH, a professor of medicine at the University of British Columbia, told Infectious Diseases in Children. “In a population health study of adolescent girls for over a decade before and after introduction of an HPV vaccine program, this study showed that adolescent girls did not make poorer sexual health choices.”

Ogilvie and colleagues sought to measure changes in sexual behaviors before and after a publicly funded, school-based HPV vaccination program for girls was introduced in 2008 in British Columbia. The researchers used data from the BC Adolescent Health Survey, which is conducted every 5 or 6 years and represents more than 1.4 million students in grades 7 to 12 in British Columbia public schools, to measure adolescent physical and emotional health. They included data from 2003, 2008 and 2013. The analysis focused on 298,265 girls aged 12 to 18 years who indicated that they were “heterosexual, unsure, questioning or without attractions.” The researchers noted that the girls who identified as lesbian or bisexual will be analyzed in a separate study. Most girls (86.8%-88%) in the study lived in urban areas.

The researchers reported a decrease in the prevalence of girls reporting ever having sexual intercourse, from 21.3% in 2003 to 20.6% in 2008 and 18.3% in 2013. Comparing data from 2003 and 2018, the adjusted OR for ever having sexual intercourse was 0.79 (95% CI, 0.71-0.88).

The researchers wrote that among girls who reported ever having sex, there was a significant decrease in reported sexual intercourse before the age of 14 between 2008 and 2013 (aOR = 0.76; 95% CI, 0.61-0.96). There was also a decrease in prevalence of substance abuse before intercourse between 2003 and 2013 (adjusted OR = 0.69; 95% CI, 0.58-0.82).

Ogilvie and colleagues also reported that there was not a significant change in the number of sexual partners reported from 2003 to 2013, and that the girls reported increased use of contraception and condoms, whereas pregnancy rates decreased.

“Parents can be reassured that the HPV vaccine does not lead to riskier sexual health decisions in young adolescent women,” Ogilvie said. – by Bruce Thiel and Erin Michael

Disclosures: Ogilvie reports antibody assay testing received from Merck that was conducted as part of an independent study monitoring antibody response to the HPV vaccine. Please see the study for all other authors’ relevant financial disclosures.