Two Professor of Psychology from the University of Austin, Texas, recently concluded their findings from a three-year study that focused on why women have sex. The study consisted of a questionnaire that asked the female participants to check off one of 237 possible reasons they attributed as a reason for sex. 1,000 women participated in the study from across various religious and cultural backgrounds. The range of reasons varied from self-gratification, to selfless pleasure of others, to experimentation, and even physiological reasons.

One stunning conclusion that broke all stereotypes was that women in their 20's are just as eager to have sex as their male counterparts. This fact put to rest the archaic idea that women are less sexually active then men in their 20's. The study found that many women in their 20's engaged just as frequently in sexual activities for reason such as, wanting to experiment, gaining more experience, or having men of different ethnicities. This point in particular may give us closer insight as to why women have casual sex with a friend.

The researchers also concluded that sexual arousal was more complicated for women than men. They found that fit men with symmetrical bodies were most attractive when it came to arousal, but that women more so then men also based attraction on a variety of personality traits such as, a good sense of humor, kindness, and confidence. While the later may seem odd from an evolutionary standpoint, the researchers concluded it actually does add up. The idea is that if a woman finds a man attractive for a broader variety of reasons the long-term affect will be a healthier relationship during child-rearing, whereas men tend to stick strictly to the fertility model of attractiveness.

Finally, the study concluded that women are much more aroused by kissing than men are, and that sex helps women to maintain a healthier lifestyle. One Rutgers University study found that women tolerate 75 percent more pain during an orgasm; meaning, sex provides women with a means of easing physical aches, such as headaches or muscle pain. Additionally, regular sex provided women with a more consistent and healthier lifecycle (sleeping, eating, and menstruating). Perhaps then the study proves that women have casual sex with a friend for physiological reasons they may be seeking that they are not even necessarily aware of.