Having sex for the first time improves the self-image of young men, but young women feel slightly worse about their appearance, according to the study. (Shutterstock)

Having sex for the first time improves the self-image of young men, but young women become "slightly less satisfied" with their appearance after they shed their virginity, a study has found.

Researchers at Pennsylvania State University surveyed 434 university freshmen -- aged 17 to 19 -- over a four-year period.

The research found that, in general, young women became more content with their physical appearance over the course of their four-year college career. Young men became less satisfied with their appearance over time.

But after the survey participants had sex for the first time, the opposite was true: the young men were more satisfied with their appearance and the the young women were less satisfied.

"We're not talking about 12-year-old girls having sex, so it's striking that even among these young women -- who are 17 or older when they first had sex -- their image of themselves went down," study author Eva S. Lefkowitz said in a release. "If on average they're feeling worse about themselves, it says something about their development of healthy sexuality and healthy sense of self and being."