NEW YORK (Reuters Health) - Girls who had been vaccinated against human papillomavirus (HPV) weren't more likely to get other sexually transmitted infections or to become pregnant, in a new study from Georgia.

That goes against worries on the part of some that getting the vaccine - which is supposed to ultimately help prevent cervical cancer - would encourage girls to become sexually active or engage in riskier sex than they otherwise would.

"Some parents have expressed it as a concern," said Saad Omer, an infectious diseases and vaccine researcher from Emory University in Atlanta who worked on the study.

"Parents can be reassured at least based on the evidence that young girls who receive HPV vaccines did not show increased signs (of) clinical outcomes of sexual activity," he told Reuters Health.

The vaccine, which has been recommended for 11- and 12-year-old girls in the U.S. since 2006, is still controversial, and only about half of girls start the series of shots.

One of the arguments against it has been that vaccination will make pre-teens feel a false sense of security when it comes to sex.