Why Women Have Sex: New Research

A 25-year-old woman has a friend who is a virgin. She's not physically attracted to him, nor does she want to be romantically involved. But she feels sorry for him, pities his inexperience. So she decides she will go home with her friend—to show him how it's done. As she undresses, she feels powerful and sexy—and that feeling (not the presence of her soon-to-be deflowered friend) turns her on. "It boosted my confidence to be the teacher in the situation and made me feel more desirable," the woman says.

The mystery of why women have sex, and what they want out of it, has long been an elusive study—something even Sigmund Freud called "the great question." Researchers have historically theorized that women's motives lie in love and commitment, while newer studies have shown they do it for pleasure, just like men. But women are complicated creatures: their sexual health is determined as much by their emotions as by their physical state, which might help explain why as many as 50 percent of women have trouble getting aroused. Yet while scientists, in recent years, have labored over the "how" of female desire, no major study, until now, has actually asked women to describe why they have sex in the first place.

In their new book, Why Women Have Sex, University of Texas psychologists Cindy Meston and David Buss aim to illuminate the complexities of women's sexual motivations through women's own words—an important step, they say, to better understanding how women can achieve sexual satisfaction. Based on five years of research and an online survey of 1,000 women, the authors consider motivation ranging from altruistic sex ("I felt sorry for the guy") to revengeful sex ("I wanted to get back at my partner") to palliative sex ("I had a migraine"). We hear from women who've had sex to boost their confidence, even if it's with a man (or woman) they find repulsive, and from those who've used sex to barter for gifts or household chores (9 percent of us have used this form of economic sex, according to a University of Michigan study). We learn that 31 percent of women have had sex to evoke jealousy in the ones they love, while others have done it to protect themselves from getting hurt. Some, like the 25-year-old woman we described earlier, have had sex to boost their self-esteem, and 84 percent of women report they've done it simply to "keep the peace" at home. "I think the stereotype tends to be that women have sex for love and men have sex for pleasure," says Meston, director of the Sexual Psychophysiology Lab at UT Austin. "But in reality, women's sexual motivations are vastly complex."

Many of those complexities, say the authors, can be explained by human evolution: stealing a friend's lover (something 53 percent have done) can be viewed as an effort to win a partner with the most desirable genes; jealousy functions to alert a person to a threat; women who have sex out of a duty to please are "mate-guarding." And while the notion that sexual decisions are tethered to our caveman (or cavewoman) past has come under recent criticism, it seems just as reasonable that the myriad of female motivations could come from the flood of mixed messages we hear about how women are supposed to behave: enjoy sex but don't enjoy it too much, withhold it but don't be a prude, save it, flaunt it, be sexy but not a slut. No wonder things get complicated.

Despite all that, the women's descriptions are fascinating—if not particularly easy to interpret. As one woman describes, "I seduced [a man who wasn't my boyfriend] to give myself the confidence that if I was dumped, I would still be able to find another partner." "I did it out of boredom, because it was easier than fighting," quips another. On one hand, the realization that women's motives can be dark and devious are likely to make many a women's advocate cringe: TV and movies joke frequently about the ways women use sex to get what they want, and female characters who manipulate are often portrayed as bitchy, heartless, or controlling. But perhaps the fact that we're hearing those motives articulated out loud for the first time is also comforting. Yes, women have sex to get what they want—and they're not always timid about it. Sometimes they do it for the emotional connection, but other times they simply want the release. (Physical pleasure and attraction, say the authors, are still the most common reasons women say they have sex.) Women are not always pure, not always transparent—and that's OK.

"Sex has all kinds of utilities—it always has," says Pepper Schwartz, a sociologist at the University of Washington and the author of a number of books on sex. "People use what they've got, and sometimes yes, women too use sexuality as a tool." Buss, an evolutionary psychologist, says, "One of the things we realized early on was that there's this huge gap in the field of study in that we thought women's sexual motivations were sort of intuitive and understood. But what shocked me was the sheer complexity of women's psychology."

Which isn't to say that male ambitions aren't multifaceted: in a 2007 survey, Meston and Buss identified 237 distinct reasons humans pursue sex, ranging from attraction—the No. 1 reason for men—to "It's fun" to "I realized I was in love" (both in men's top 20 reasons). But the brain is the primary driver of female arousal, which means we tend to overanalyze and dissect, to the point that our motivations, in many cases, have very little to do with simple physical desire. We also have anatomical differences: if a man gets an erection (which can occur easily from acts unrelated to sex) it generally triggers sexual desire. Not so in women. And while the wonder drug Viagra has enhanced sex for millions of happy men, simply increasing a woman's blood flow will cure little. More than half of women under 60 still suffer from low sex drive, and a quarter are unable to orgasm. "I could write a book about this alone," says Meston. But "sexual behavior is more contextual for women."

The women who answered Meston and Buss's online survey certainly don't represent every woman, says Julia Heiman, the director of the Kinsey Institute for Research in Sex, Gender and Reproduction. Nor will an anonymous online poll tell us everything we need to know. The authors are well aware of that reality, but it is a start. "Up until the past 10 years, we weren't even talking about the nuances of female sexuality, let alone the multifaceted reasons we have sex," says Laura Berman, a professor of psychiatry at Northwestern University and the author of Real Sex for Real Women. "So in that sense, this is a really big step." A step, with many more to go.