TUESDAY, April 10 (HealthDay News) -- Male teens who were sexually abused are more likely to have unsafe sex, a new study finds.

University of British Columbia researchers analyzed data from more than 40,000 American and Canadian male high school students who were surveyed between 1986 and 2011.

Compared to those with no history of sexual abuse, young males who were sexually abused were five times more likely to cause teen pregnancy, three times more likely to have multiple sexual partners and two times more likely to have unprotected sex, according to the study published online and in the June print issue of the Journal of Adolescent Health.

"As far as we know, this is the first study to explore the strength of the effects of sexual abuse on boys' sexual behavior," lead author Yuko Homma, a recent Ph.D. graduate from the University of British Columbia's School of Nursing, said in a university news release. "Our findings show that boys are also vulnerable to the traumatic effects of sexual abuse, which can lead to sexually transmitted infections or teen pregnancy."

About 8 percent of males and 20 percent of females in North America report that they've been sexually abused.

"Boys are far less likely to tell someone when they have been sexually abused," study co-author Elizabeth Saewyc, a UBC professor of nursing and adolescent medicine, said in the news release. "Yet it's clear they too need support and care to cope with the trauma from sexual violence."

Homma agreed. "Parents need to speak to their sons about sexual abuse awareness and prevention, as parents of girls do. Boys may hesitate to tell parents about an incident if parents have misconceptions about sexual abuse -- that it can't happen to males."

The researchers also suggested that schools should include sexual abuse prevention in health education, and health care agencies should screen boys and girls for a history of sexual abuse.

More information

The American Academy of Pediatrics has more about sexual abuse.