Seems like a no-brainer -- we have sex to reproduce and for pleasure. However, the reasons we have sex are more complex. A study published in the scientific journal Archives of Sexual Behavior has identified 237 expressed reasons for having sex.

Researchers sorted those reasons into four factors (and 13 subfactors): physical (stress reduction, pleasure, physical desirability, experience seeking); goal attainment (resources, social status, revenge, utilitarian); emotional (love and commitment, expression); and insecurity (self-esteem boost, duty/pressure, mate guarding).

There were considerable differences between men and women, but they are perhaps not that surprising. Physical reasons were important to men; emotional reasons were important to women.

Top 10 Reasons for Women
• I was attracted to the person
• I wanted to experience the physical pleasure
• It feels good
• I wanted to show my affection to the person
• I wanted to express my love for the person
• I was sexually aroused and wanted the release
• I was “horny”
• It’s fun
• I realized I was in love
• I was “in the heat of the moment”

Top 10 Reasons for Men
• I was attracted to the person
• It feels good
• I wanted to experience the physical pleasure
• It’s fun
• I wanted to show my affection to the person
• I was sexually aroused and wanted the release
• I was “horny”
• I wanted to express my love for the person
• I wanted to achieve an orgasm
• I wanted to please my partner