People who use condoms every time they have sex could significantly decrease their chances of becoming infected with human papillomavirus, or HPV, according to a recent study at the University of Washington.

Researchers studied 82 female students at the university and found the women whose partners always used condoms were 70 percent less likely to get the virus than the women whose partners used condoms less than 5 percent of the time.

Even women who used condoms more than half of the time were still 50 percent less likely to contract the virus, according to the study published by The New England Journal of Medicine on Thursday.

The study monitored the sexual activities of the women — ages 18 to 22 — by way of electronic diaries. All of the women studied were either virgins or had sex with only one male partner within the three months before the study began.

HPV is a group of more than 100 viruses, about 30 of which can be passed sexually. Men can also pass the virus to women from sores on the outside of their genitals . The study, however, found that the chances of HPV being spread this way appear to be small.

"People have thought that condoms theoretically should prevent HPV, but because there hadn't been any specific evidence, that was still debatable," said Dr. Rachel Winer, the lead author of the study.

Winer said the research can stand fairly well by itself as evidence that condoms greatly reduce the risk of acquiring HPV, although additional studies on women of different age groups and economic status will provide further information.

Certain strains of HPV are recognized as the major cause of cervical cancer. The recently approved Gardasil vaccine protects women from 70 percent of the strains that lead to cervical cancer and 90 percent of the strains that lead to genital warts.

All past studies on the effectiveness of condoms in preventing the spread of HPV showed no connection or came back inconclusive.

Dr. Alice Penrose, a doctor of internal medicine at the Ingham County Health Department, said the study provides more reliable information than past studies because of how it was conducted. Penrose said HPV is so common and can be contracted so easily, that studying virgins makes the study far more effective than past research.

"If you get a woman who has been sexually active for a year or so, she's probably already been exposed (to HPV), so it's very important to start with women who haven't had any sexual contact," Penrose said.

Another effective measure the study took was having the women record their activities in electronic journals instead of with face-to-face interviews.

"Saying 'Oh yeah, I forgot to use a condom this week' is easier to put into a computer than admit to a physician," Penrose said.

Nicolle Stec, a sexual health educator at the Olin Health Center, said the study is a good step toward measuring just how effective condoms are in preventing HPV.

"It's information in a new form because it actually has numbers attached to it," she said. "One study is just the beginning — it's opening a window to see what's going on," she said.

The Associated Press contributed to this report.