Dr. Meana, a professor of psychology at the University of Nevada at Las Vegas has been studying women and sexual desire for 20 years. She says that while moments of pleasure are great, it's the anticipation and buildup to those moments that really excite women. "I'm not knocking orgasms," she says. "But being desired is extremely arousing for women. The reason for that is that being desired means that a man doesn't just want to have sex. He wants to have sex with you."

That specificity is what women strive for, Dr. Meana says. "If you look at how women behave and what we spend our time and energy and lots of money on, it's on desire-creating behaviors rather than on trying to get sex."