Study finds fewer HPV doses still effective

2 doses instead of 3 provides considerable reduction in risk

A new Swedish study finds getting the recommended three doses of HPV vaccine provides maximum protection from genital warts, a symptom of the human papillomavirus,  but getting only two doses still provides a considerable reduction in risk, particularly among women who were younger than 17 when they received their first dose.

"Three shots works best. Two shots works OK. One, not so much, kids are still getting warts," explained Cleveland Clinic Children's pediatrician Dr. Ellen Rome.

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Researchers at Karolinska Institute in Stockholm looked at the association between the number of doses of HPV vaccination and genital warts among females 10 years old to 24 years old. They found among the more than 20,000 new cases of genital warts, 322 occurred after receiving at least one dose of the vaccine.

Researchers say maximum risk reduction occurs with three doses, but there was a small difference in the number of cases prevented by three doses versus two. Researchers concede their study looked at genital warts only and not the risk of cervical cancer.

Rome says that's why it's important to get your teen the vaccinations they need.

"All 3 shots- ideally by age 14. You don't wait for a tetanus booster until they've stepped on a nail. Similarly, we want all three HPV vaccines in them long before they're thinking about sex," Rome said.

Complete findings for this study are in the Journal of the American Medical Association.

Read more about HPV here.