Sex more fun with someone else

I, Science 20 March 2006
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Sex could be 400 percent more satisfying than masturbation, according to new research published in Biological Psychology.

Researchers measured blood levels of prolactin, a hormone released after orgasm, which induces a feeling of satisfaction.

Prolactin levels in both sexes were found to be 400 percent higher following an orgasm from sexual intercourse than one from masturbation.