TUESDAY, April 24, 20112 (MedPage Today) — That elusive sexual will-o’-the-wisp, the G-spot, has been found. It just wasn’t where anyone had looked.

It’s the first anatomic evidence of the G-spot, which has been the subject of controversy for decades, according to Adam Ostrzenski, MD, PhD, of the Institute of Gynecology in St. Petersburg, Fla.

Despite intense interest, previous research had not found the spot — largely, Ostrzenski wrote online in the Journal of Sexual Medicine, because surgeons have been looking in the wrong place.

Ostrzenski's research indicates the G-spot is a sac-like structure, measuring 8.1 millimeters long, and made of what appears to be erectile tissue. Ostrzenski located it in the dorsal perineal membrane of the front vaginal wall.

Ostrzenski described the structure as having a “bluish grape-like composition” with three distinct parts – a head, middle, and tail – with a rope-like vessel emerging from the tail into the surrounding tissue.

The G-spot has been the topic of intense discussion for decades — called the fount of sexual pleasure for women by some and dismissed as a mirage by others.

“The absence of the identification of the G-spot as an anatomic structure created considerable controversies,” Ostrzenski said.

Pinning it down, he concluded, could have an important “potential impact on the practice and clinical research in the field of female sexual function.”

He found the structure after careful, layer-by-layer dissection of the anterior vaginal wall of an 83-year-old woman who had died of head trauma, he reported.

Surgeons making repairs usually dissect the anterior wall only to the level of the pubocervical fascia, he noted. But since there have been no reports of a structure that could be the G-spot in that region, he hypothesized it would be found higher up.

And indeed, he reported, there it was – on the superior surface of the dorsal perineal membrane – the area between the openings of the vagina and the rectum — about 16.5 millimeters (just over a half-inch) from the upper part of the urethral opening.