Okay, so sometimes you're just in the mood and that's all there is to it. But it turns out women also have sex for a variety of other reasons, including feeling sorry for the guy, wanting to cure a headache, and hoping that a romp will get him to, say, mow the lawn or fix the peeling wallpaper in the bathroom. At least that's what University of Texas psychologists Cindy Meston and David Buss found after surveying 1,000 women on what motivated them to get it on. What do you think? Have you ever slept with your husband to get him to do something for you, or to simply relieve those PMS cramps?

It turns out that there are a total of 237 reasons people have (or at least pursue) sex, including the obvious -- attraction -- but also the not-so-obvious, such as getting back at someone or simply being drunk or getting carried away. Nine distinct themes emerged, including experiencing pleasure, expressing love, marking a special occasion, or even just that the "opportunity presented itself." Want to know more? Check out Meston and Buss' new book Why Women Have Sex, and share your own opinions below.

-- The Nest Editors

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