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Get out your measuring sticks. Turns out, size may matter – only not in the way most people think.

Surprisingly, a woman’s ease of orgasm may boil down to her own measurements and not his.

New research from Kim Wallen, a professor of psychology and behavioral neuroendocrinology at Emory University, indicates that the distance between a woman’s clitoris and vagina may determine how easily she climaxes from sex alone.

Length and girth have long been considered when it comes to satisfying sexual pursuits. The Kamasutra of Vatsyayana explains “ideal” sexual unions along the lines of size.

Naturally, equal unions are considered best. And over the years, modern couples have questioned the adequacy of his size if sex is “off” or parts don’t fit well together.

But is it really her size that’s throwing things off?

Modern and early 20th Century research indicates that women with a distance of 2.5 centimeters between clitoris and vagina have the best chances of achieving orgasm from sex alone.

“Téléclitoridienne,” a term meaning “female of the distant clitoris,” was first studied last century. According to “Bonk: The Curious Couple of Science and Sex,” the term was coined in the 1920s by Princess Marie Bonaparte, the great grand niece of Napoleon. This psychoanalyst was considered a sex researcher in her own right.

Unhappily married to George of Greece, a latent homosexual, and suffering from anorgasmia (lack of orgasm), after a number of affairs, Marie worried that she was “frigid” and wanted scientific proof.

So she came up with an anatomical theory that women with the lengthiest distance span between their clitoris and vagina (that of more than 2.5 centimeters) were rendered incapable of climax during intercourse.

To prove her hypothesis, Bonaparte interviewed and measured 243 females in 1924 that were incapable of having an orgasm during intercourse. Working with doctors, she actually measured these women, finding that 21 percent of the sample fell into the téléclitoridienne category.

The 69 percent of women in her sample who could have orgasms during sex had significantly smaller distances between sex organs. These women, referred to as paraclitoridiennes, could almost always climax from sex.

Bonaparte also found a correlation between a woman’s height and the closeness of her sex organs. This was namely that shorter women tended to have shorter spans.

Wallen analyzed Bonaparte’s measurements with modern statistical techniques and found she just might be right.

Wallen estimates that the most easily attainable orgasms from sex are attributed to clitoris-vagina distances that are about the size of a thumb. Anything over that is likely to require a little more technical assistance, which it seems the vast majority of lovers will require.

In researching the matter himself, Wallen’s preliminary findings show that no more than approximately 7 percent of females consistently reach climax from sex alone.

Bummer.

Dr. Yvonne K. Fulbright is a sex educator, relationship expert, columnist and founder of Sexuality Source Inc. She is the author of several books including, "Touch Me There! A Hands-On Guide to Your Orgasmic Hot Spots."

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