Why Women are Too Tired for Sex

May 10, 2011

Men around the world are familiar with the excuse, “Baby, I’m just too tired for that tonight.” Well, now there’s a scientific reason why women are too tired for sex and it offers unfulfilled men some hope.

Researchers at Harvard University have discovered a scientific reason for why women are sometimes too tired for sex at the end of the day. It turns out women run on a quicker biological sleep clock than men and need to go to bed earlier because of it. The study found women are often “chronically sleep-deprived because they try to fight against their faster sleep cycles.”

The study was conducted with 157 people who spent eight weeks in a windowless sleep lab in Boston at the Harvard-affiliated Brigham and Women's Hospital. Jeanne Duffy, study co-author from Harvard, said: “What we found was that the cycle length of the biological clock in women was shorter on average than it was in men. The average difference was about six minutes.” This means some women complete their daily cycle in less than 24 hours.

Women are therefore much more likely to be early birds than night owls. This is good news for men, as the study found women are likely to be more “awake” in the morning and therefore more likely to get frisky.

Bring on the morning sex!

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