The elusive G-spot has been called the UFO of gynecology -- but now a retired surgeon says he has photographic proof it exists.

The alleged G-spot is a tiny bunch-of-grapes-like structure within a bluish sac buried deep within the front wall of the vagina, says Adam Ostrzenski, MD, PhD, of St. Petersburg, Fla.

"As an erectile body, this structure is causing elevation of the [front of the] vaginal wall at the beginning of the sexual excitement," Ostrzenski tells WebMD.

G-Spot? Maybe Not

But Ostrzenski's finding is based on a single dissection, performed on a recently deceased 83-year-old woman.

"The feeling in my limited field is that this is not real," Elena Ratner, MD, assistant professor of obstetrics, gynecology, and reproductive medicine at Yale University, tells WebMD via email.

Ratner notes that findings from a single dissection, performed on an elderly woman, are not proof that the structure is common to all women -- or that it is a source of sexual sensation.

"Who is to say that this thing they found on her dissection was the center of pelvic pleasure?" Ratner asks.

Even more dismissive of Ostrzenski's claim is sex therapist Leonore Tiefer, PhD, clinical associate professor of psychiatry at New York University Medical Center.

"We can conclude absolutely nothing from this paper since we know nothing about the sexual life of the dead woman," Tiefer tells WebMD via email.

While warning that nothing is proven by a single case, Christopher Estes, MD, assistant professor of obstetrics and gynecology at the University of Miami, does not dismiss Ostrzenski's report.

"This certainly is suggestive of an anatomical structure that would correlate with a G-spot," Estes tells WebMD. "Women who experience orgasms from a G-spot will describe a hardening on the inside of the vagina, a little almond- or peanut-shaped protuberance. This is consistent with that."

The G-spot, in 1981 named the Grafenberg zone after Ernst Grafenberg, was christened the "G-spot" in media reports. The area, variously described as somewhere in the front of the vagina, is a source of sexual stimulation to about 50% of women.

But whether there is an anatomical structure corresponding to this sensation, or whether stimulation simply affects other sensitive areas of a woman's anatomy, remains a matter of controversy.

There is no scientific evidence that any gynecologic procedure can enhance a woman's G-spot sensitivity. But many gynecologic surgeons offer such procedures. Ostrzenski himself performed such operations, according to his resume. And the surgeon who photographed his dissection, Mark Scheinberg, MD, offers women collagen injections -- the controversial "G-shot" -- at his clinic in Deerfield Beach, Fla.

And Ostrzenski says he's working on a new procedure to improve G-spot sensitivity in women whose vaginal structure is "distorted." He plans to call it "G-Spot Plasty."

X Marks the G-Spot

If Ostrzenski has indeed located the anatomical G-spot, why hasn't anybody else found it?

Ostrzenski says that during his long career as a gynecologic surgeon, he's found that textbooks often are inaccurate about the details of female sexual anatomy.

After deducing that the G-spot must lie deep beneath the muscles of the vaginal wall, Ostrzenski reasoned that the structure, if it existed, could only be found in a fresh corpse not yet fixed with tissue-altering formaldehyde.

In his seven-hour dissection, the Poland-trained surgeon carefully cut away layer after layer of the vaginal wall. He cut through five layers of tissue and muscle to reveal a bluish sac sitting atop a structure called the perineal membrane.

After opening the sac, Ostrzenski found a bluish tissue resembling a tiny bunch of grapes with a white rope-like tail. It was less than a third of an inch long, from 0.14 to 0.05 inches wide, and 0.016 inches tall.

"This is definitely not anywhere near a routine dissection," Estes says. "The structure itself is very, very small. I could see that unless you were very, very careful, you could easily go right through the tissues and not find it."

How can something that small play a role in sexuality? Ostrzenski says the tissue looks like erectile tissue. Under pressure, he speculates, the tissue would lift the vaginal wall, either triggering sensations around the clitoris or possibly sending out its own set of sexual sensations.

But Estes notes that "the actual role this structure plays in sexual function is hard to say."

Ostrzenski's report appears in the May issue of the Journal of Sexual Medicine.

SOURCES:Ostrzenski, A. Journal of Sexual Medicine, May 2012.Adam Ostrzenski, MD, PhD, St. Petersburg, Fla.Christopher Estes, MD, assistant professor, ob-gyn, University of Miami Miller School of Medicine, Miami.Leonore Tiefer, PhD, clinical associate professor of psychiatry, NYU Medical Center, New York; email correspondence.Elena Ratner, MD, assistant professor of obstetrics, gynecology, and reproductive medicine, Yale University, New Haven, Conn.

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