Study after study shows that men's sex drives are not only stronger than women's, but much more straightforward.But women also appear to be heavily influenced by social and cultural factors as well.
Bear in mind that people may vary from these norms.
The majority of adult men under 60 think about sex at least once a day, reports Laumann.
Only about one-quarter of women say they think about it that frequently.
As men and women age, each fantasize less, but men still fantasize about twice as often.
In a survey of studies comparing male and female sex drives, Roy Baumeister, a social psychologist at Florida State University, found that men reported more spontaneous sexual arousal and had more frequent and varied fantasies.
"Men want sex more often than women at the start of a relationship, in the middle of it, and after many years of it," Baumeister concludes after reviewing several surveys of men and women.
"Sexual desire in women is extremely sensitive to environment and context," says Edward O. He is a professor of sociology at the University of Chicago and lead author of a major survey of sexual practices, The Social Organization of Sexuality: Sexual Practices in the United States.
Here are seven patterns of men's and women's sex drives that researchers have found.
They are likely to be more attuned to relationship quality because they want a partner who will stay around to help take care of the child.