By Dr. Richard Rupp and Bridget Hawkins, Ph.D.  

Dear Vaccine Smarts,

I didn’t vaccinate my teenage daughter against HPV because I was worried that it would encourage her to become sexually active. I was having second thoughts about my decision after hearing about actor Michael Douglas’s throat cancer. Can you tell me more?


Dear Yvonne,

Good question. Did you know there are more than 100 different types HPV, or human papillomavirus? Some cause warts on the hands and feet while others grow only in the throat, anus and genitals. Some types can lead to cancer if the infection persists more than a couple years.

Remarkably, about 80 percent of people will be infected with at least one of the sexually transmitted types of HPV during their lifetime.

The vaccines that are currently licensed in the United States prevent the two HPV types that cause the most cancer. They’re recommended for females ages 11-26 and males ages 11-21.

Some parents, like you, worry that vaccinating teens will encourage sexual activity, but these fears appear to be unfounded.

A study published in the October 2012 issue of Pediatrics looked at almost 1,400 vaccinated girls. What the researchers found was that the vaccinated girls were no more likely to become pregnant, develop a sexually transmitted infection or seek birth control than their unvaccinated peers.

The findings are not surprising. Teen decision-making about whether to initiate sexual relations is complicated and unlikely to be affected by having been vaccinated for HPV.

Parenting and clear communication are more likely to influence teens. Parenting refers to monitoring a teen’s activities and keeping him or her out of risky situations, such as being left unsupervised with a boy or girlfriend.

We know it can be awkward for parents to discuss sex with their children, but it’s so important. Teens need to know what their parents expect from them.

Here’s something interesting: Most parents report that they have talked about sex with their teens, but many teens report that their parents have never spoken to them about sex or, if they did, the teens received a different message than was intended by the parents.

For example, a parent reported delivering an abstinence (no sex) message. Because of miscommunication, the teen later reported that the parent gave the “go ahead.”

Repeated discussions may be the way to make sure that the messages are received as they are intended.

In addition to talking with your daughter, we do advise vaccinating her now. Research shows younger teens have a better immune response to the vaccine. As far as we know today, full protection is only achieved after having received the full three-shot series.

Parents often want to hold off until their teen is sexually active, but keep in mind that the vaccine can only prevent infection and does not treat infections. Additionally, intercourse is not the only way the virus can be spread. It can spread by kissing, petting and contact with infected objects like underwear.

When you vaccinate your daughter, we suggest you emphasize that it’s for her protection later in life and have a discussion with her about your expectations and family values.

Dr. Richard Rupp is a pediatrician and member of UTMB’s Sealy Center for Vaccine Development. Bridget Hawkins, Ph.D., is the assistant director of the Sealy Center for Vaccine Development. This column is supported by a UTMB President’s Cabinet Award to provide information about vaccines. Visit for more information.