Despite fears to the contrary, sexual behaviours of adolescent girls stayed the same or became safer after publicly funded school-based HPV vaccinations were introduced in British Columbia (BC), according to new research published in CMAJ (Canadian Medical Association Journal).

Some groups have been concerned that HPV vaccination could encourage early sexual activity, unprotected sex and other risky sexual behaviours.

"The HPV vaccine has proved to be a remarkably effective and safe vaccine. However, parents have expressed concern that the use of the HPV vaccine might promote or condone risky sexual behavior in adolescents," explains lead author Dr. Gina Ogilvie, of the School of Population and Public Health, the University of British Columbia, and assistant director of the Women's Health Research Institute at BC Women's Hospital, Vancouver, BC.

In 2008, BC introduced a publicly funded routine HPV vaccination program in schools for girls in grades 6 and 9. After 2011, the program was available only for girls in grade 6.

Researchers looked at data from the BC Adolescent Health Survey, a comprehensive population-based survey of students in grades 7 to 12 conducted every five years by the McCreary Centre Society. Girls from the 2003, 2008 and 2013 surveys were included, representing the more than 300,000 girls enrolled in public schools across the province. The percentage of girls who reported ever having sex decreased from 21.3% in 2003 to 20.6 % in 2008 and to 18.3% in 2013. As well, the proportion of girls having intercourse before age 14 declined between 2008 and 2013, and the use of condoms increased over time, from 65.6% in 2003 to 68.9% in 2013.

"Our analyses of data from this province-wide survey suggests that implementing a school-based program for HPV vaccination did not lead to an increase in risky sexual behaviours among adolescent girls at the population level," notes study co-author Dr. Elizabeth Saewyc, of the School of Nursing, University of British Columbia. "These findings should help allay any parent or provider fears that participating in HPV vaccination might increase sexual behaviours among teenaged girls."