HPV Vaccine Doesn't Encourage Teen Girls to Have Risky Sex

Receiving a vaccine that protects against a cancer-causing virus spread through sexual contact does not result in teenage girls engaging in risky sexual behavior, a study has found.

The human papillomavirus (HPV) can cause cervical cancer, the fourth most common cancer in women, which killed an estimated 266,000 women in 2012, according to figures from the World Health Organization. Spread through sexual contact, almost every case of cervical cancer is associated with HPV. The virus can also cause head, neck and anogenital cancers, as well as genital warts in women and men.

The HPV vaccine is recommended for young girls aged nine to 14. However, due to the sexual transmission of the virus, the rollout of the vaccine has stoked fears among parents it could encourage young girls to engage in what are known as risky sexual behaviors, such as unprotected sex, having many sexual partners and starting sexual contact at an early age.

In a study published in the Canadian Medical Association Journal, researchers focused on the population of British Columbia, Canada.

"In British Columbia, we continue to struggle with our HPV vaccine uptake rates, with rates [at less than] 70 percent," Dr. Gina Ogilvie, lead study author at the School of Population and Public Health at the University of British Columbia, and assistant director of the Women's Health Research Institute at BC Women's Hospital, told Newsweek.

"When parents are asked why they are hesitant to have their children receive the vaccine, one of the key issues they identify is the concern that the vaccine will encourage children and adolescents to make poorer sexual health choices."

The team set out to investigate whether such concerns were valid by comparing the sexual behaviors of teenage girls before and after the vaccines were introduced in schools.

The vaccine program began in BC in 2008 for girls in sixth to ninth grade, and those in sixth grade in 2011. The team analyzed data on almost 300,000 girls who completed the BC Adolescent Health survey, which asked school children about their emotional and physical health in 2003, 2008 and 2013. The girls self-identified as heterosexual.

From 2003 to 2013, the proportion of girls who had sex dropped from 21.3 to 18.3 percent. Girls who had sex before the age of 14, and used substances before intercourse "dropped significantly," the authors of the study wrote. Girls were more likely to use condoms and contraception in 2013 than 2003. Rates of pregnancies fell, while the average number of sexual partners remained largely the same.

Study co-author Dr. Elizabeth Saewyc, of the School of Nursing, at the University of British Columbia, told Newsweek: "These findings are consistent with studies in Scandinavia, and smaller clinic-based studies in the U.S., that confirm that adolescent young women do not make poor sexual health choices after the HPV vaccine. Teens today make healthier decisions about sex than their older peers—or even their parents."

As vaccine programs were prioritized for girls and rolled out for boys later, the effect on both sexes is another important area of research, said Saewyc.

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Dr. Cynthia Holland-Hall, associate professor of Clinical Pediatrics at The Ohio State University College of Medicine, who was not involved in the research, told Newsweek the study mirrors prior research on HPV and risky sexual behaviors.

"Most of those prior studies have been observations at a single point in time. This study is unique in that it looks at sexual behaviors in a single, large population of girls both before and after the implementation of a school-based HPV vaccination program. The investigators found that despite relatively high vaccination rates, the overall prevalence of risky sexual behaviors actually declined in this population after the implementation of the vaccine program.

"This goes to show that there is far more that goes into girls' sexual decision making than whether or not they have been vaccinated against HPV. Other personal, societal, and cultural factors play a much greater role," said Holland-Hall.

Dr. Jonathan D. Klein, professor in the department of pediatrics at the University of Illinois at Chicago and immediate past-chair at NCD Child, who was not involved in the study, told Newsweek: "Vaccination does not encourage promiscuous sexual activity anymore than fire extinguishers encourage people to set fires or seat belts encourage people to have car accidents. Sexuality education is important for young people and is recommended by all of the major pediatric and medical organizations as well as by global and national public health agencies."

Meanwhile in Australia, the successful HPV vaccination program could wipe out cervical cancer within the next 20 years according to a study published in the The Lancet Public Health journal. Cases could drop to less than four in 100,000 in 2035 if current trend continues.