Mapping the way to G-spot utopia

To Jannini, it's clear: Some women have extra-thick, sensitive, different tissue in the front wall of the vagina, whose stimulation can lead to vaginal orgasms. Other women don't. (Call it a G spot if you like, he says; until there's a formal definition, the label is more about marketing than science.) Figuring out once and for all which group a woman is in might someday be done with a detailed biochemical analysis and ultrasound imaging.

Thick or thin, though, it's all part of natural variability, Jannini believes. "A woman without the so-called G spot is perfectly normal," he says. Exactly why tissue in this region would be thicker in some women isn't clear, though their natural testosterone levels may be involved. His team is now investigating how too much or too little of the hormone might change this tissue size.

But there are probably no shortcuts to this kind of plumped-up G spot. Some cosmetic surgeons offer "G-Shots" -- injections of collagen into vaginal wall tissue -- though there's no published evidence showing they create a more sensitive vagina. Nor is there any reason to suspect they would, Jannini says. A thicker G spot is more sensitive because of the chemically active tissue naturally there. Inserting a blob of foreign material won't change that, he says.

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Variability as the rule

Although intriguing, the G-spot ultrasound study is far from definitive, researchers say. It's hard to draw conclusions from the small number of participants, for one thing. And the study didn't explore whether the women's vaginal orgasms were in fact due solely to stimulation of the front vaginal wall or if other parts of the vagina or cervix were involved. Plus, the thickness of women's tissue probably lies along a continuum, reflecting to some degree the amount of sensitivity within.

In fact, sexual variability seems to be the rule among women, says Kim Wallen, a psychology professor at Emory University. He has explored the methods women use to experience orgasm, and how the configuration of a woman's external clitoris and vagina relate to her orgasms during intercourse. In recent work, published in February in the journal Evolution and Development, he and a colleague found that the women's clitorises vary in length about three times more than men's penises do. This might relate to why the G spot differs so wildly among women, he says -- and also hint as to why its absence need not matter so much in practice.

"Our work has shown that the variability in women's orgasms is quite remarkable," Wallen says.

"Women's potential to have different kinds of sexual experiences is probably greater than it is in men. And the variability in women's genitalia may also reflect that there are more paths to orgasm in women than in men."

Or, as Ernst Grafenberg wrote, "There is no spot in the female body, from which sexual desire could not be aroused."

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