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Coni Butler, an accountant in Austin, Tex., and a devout Catholic, encourages her three children to remain celibate before marriage. But that did not stop her from getting them vaccinated against human papillomavirus, or HPV, a sexually transmitted disease that raises the risk of some cancers.

Ms. Butler had her son and two daughters vaccinated between ages 12 and 15. She was not deterred by widespread concerns that the vaccine might encourage promiscuity.

“We talk about remaining chaste until they get married, but there’s always the possibility that one bad choice could lead to devastating consequences,” she said. “I tell my friends that you pray for the best, but you plan for the worst.”

Since public health officials began recommending in 2006 that young women be routinely vaccinated against HPV, many parents have hesitated over fears that doing so might give their children license to have sex. But research published on Monday in the journal Pediatrics may help ease those fears.

Looking at a sample of nearly 1,400 girls, the researchers found no evidence that those who were vaccinated beginning around age 11 went on to engage in more sexual activity than girls who were not vaccinated.

“We’re hopeful that once physicians see this, it will give them evidence that they can give to parents,” said Robert A. Bednarczyk, the lead author of the report and a clinical investigator with the Kaiser Permanente Center for Health Research Southeast, in Atlanta. “Hopefully when parents see this, it’ll be reassuring to them and we can start to overcome this barrier.”

HPV, the most common sexually transmitted virus in the United States, can cause cancers of the cervix, anus and parts of the throat. Federal health officials began recommending in 2006 that girls be vaccinated as early as age 11 and last year made a similar recommendation for preadolescent boys. The idea is to immunize boys and girls before they become sexually active to maximize the vaccine’s protective effects.

According to research, nearly a third of children 14 to 19 years old are infected with HPV. But despite the federal recommendations, vaccination rates around the country remain low, in part because of concerns about side effects as well as fears the vaccine could make adolescents less wary of casual sex. In one study of parental attitudes toward the vaccine, Yale researchers found that concern about promiscuity was the single biggest factor in the decision not to vaccinate. (A report last year from the Institute of Medicine, which advises the government, found that that the HPV vaccine was generally safe.)

While there have been studies suggesting that the vaccine does not lower inhibitions in girls who receive it, most of them were based on self-reporting, which is not very reliable. So Dr. Bednarczyk and his colleagues looked instead at medical data collected by a large managed care organization.

They selected a group of 1,398 girls who were 11 or 12 in 2006 — roughly a third of whom had received the HPV vaccine — and followed them through 2010. The researchers then looked at what they considered markers of sexual activity, including pregnancies, counseling on contraceptives, and testing for or diagnoses of sexually transmitted diseases.

Over all, in the time that the girls were followed, the researchers did not find any differences in these measures between the two groups.

In addition to the HPV vaccine, federal guidelines also call for 11-year-olds to be immunized against meningitis, tetanus, diphtheria and pertussis. Dr. Elizabeth Alderman, president of the North American Society for Pediatric and Adolescent Gynecology, said parents almost never object to those vaccines for their preadolescents. But she regularly encounters parents who balk at the HPV vaccine “because of the nature of what it’s preventing.”

“I’ll now be able to use this study as a piece of evidence to show them that it’s not going to give girls a license to sexual activity,” said Dr. Alderman, an adolescent medicine specialist at Children’s Hospital at Montefiore Medical Center in New York.

Dr. Jonathan Temte, a family doctor in Wisconsin who is chairman of the United States Advisory Committee on Immunization Practices, said he tells skeptical parents in his practice to think of vaccination no differently from wearing a helmet to ride a bike or play football.

“By providing this protection, are we encouraging kids to take more risky behaviors?” he said. “I don’t believe so.”