Teens who skip school and fail tests are more likely to engage in risky sexual behavior, according to a recent study.

Researchers from Indiana University found that vaginal sex is more frequent and condom use was less frequent among 14- to 17-year-old girls who skipped school and failed tests.

"This study demonstrates that young women's weekday reports of skipping school and failing a test were significantly linked to more frequent vaginal sex, less frequent condom use and different sexual emotions, on that same day," Devon J. Hensel, lead author of the study, said in a statement.

For the study, Hensel and his colleagues combed through about 80,000 diary entries written by 14- to 17-year-old girls and examined the day-to-day relationship between teenage girls' reports about school-related events, how they felt and the sexual behaviors they participated in. The findings are based on a 10-year study of the development of 387 teenage girls' romantic relationships and sexual behavior.

Prior studies have shown that academic success is linked to lower sexual risk, but researchers have relied on retrospective information, Hensel added.

"Romantic relationships become a primary social focus during adolescence, and school provides a venue where young women meet and interact with their partners," Hensel said. "Many of the same skills underlying academic outcomes -- such as communication, emotional awareness and behavior regulation -- are also linked to what happens in young women's relationships. Using this idea, we hypothesized that what happened academically during a given school day would impact how an adolescent felt about her romantic partner, and the behaviors she engaged in with that partner

Academic behaviors included skipping school and failing a test; sexual behaviors were vaginal sex and condom use; and emotions involved positive mood, negative mood, feeling in love, sexual interest, partner support and partner negativity.

Researchers found that vaginal sex was more frequent (13.5 percent vs. 5.4 percent) and condom use was less frequent (13.8 percent vs. 33.1 percent) on weekdays when school was skipped as compared to weekdays when school was attended. However, incidents of vaginal sex did not vary if the diary author failed or did not fail a test (6.4 percent vs. 5.8 percent); but when sex did occur, condom use was less frequent when she failed a test (6.9 percent) compared to when she did not (27.1 percent).

Emotionally, young women reported significantly higher levels of negative mood, sexual interest and feeling in love, and lower levels of positive mood, on weekdays when they skipped school or failed a test, as compared to weekdays when neither of these events occurred.

Researchers said their results raise the possibility that the emotional and behavioral experiences in young women's romantic and sexual relationships may impact her reaction to academic events, particularly if an event is more salient to her or to her partner.

"For example, condom use might be lower after failing a test if a young woman feels supported and loved by her partner," Hensel summarized.

The findings were recently published in the Journal of Adolescent Health.