G-Spot

# Overview
The Grafenberg spot, or G-spot, is an erogenous zone that when stimulated leads to high levels of sexual arousal and powerful orgasms.

# Origin and popularity of the term
The term "G-spot" was coined by Addiego et al. in 1981. It is named after the German gynaecologist Ernst Grafenberg who first hypothesized its existence in 1944. The G-spot's existence was not disclosed until the next year, with the publication of The G Spot and Other Recent Discoveries About Human Sexuality by Ladas et. al. Shortly after publication of Ladas's book, many gynaecologists publicly criticized its scholarship and accuracy..

## Location of the spot
The purported location of the G-spot has changed over time. Two primary methods have been used to attempt to locate it:
- The first is based on self-reported levels of arousal during stimulation and
- the second based on the claim that stimulation of the G-spot leads to female ejaculation.
One of the studies using self-reported levels of arousal was a case study with a single woman who claimed the experience of a deeper orgasm when her G-spot was stimulated. In the published study it was reported that stimulation of the anterior vaginal wall made the area grow by fifty percent.
Another study examined eleven women in an attempt to locate the spot under laboratory conditions. Researchers attempted to find the G-spot by palpating the entire vagina in a clockwise fashion. Using this technique the researchers reported discovering that four of the women had highly sensitive areas on the anterior vaginal wall.

## Public belief
Despite professional and scientific criticism and skepticism, the G-spot, as a concept, was widely accepted by the public. One study reports that 84 percent of women believe that there is a highly sensitive area in the vagina. Most popular sexology books treat the G-spot as real.

## Scientific evidence
Subsequent empirical investigations of the G-spot have yielded variable results. Tests that examined the vaginal wall innervation show there is no one area with a greater density of nerve endings. A recent study of 110 biopsy specimens drawn from 21 women concluded with the absence of a vaginal locus with greater nerve density. G-spot proponents are criticized for placing too much credence upon anecdotal evidence from women.
The few studies attempting to locate the G-spot more precisely have yielded positive evidence, yet only from small participant samples, and have been criticized for the use of questionable investigation methods..  A recent ultrasonography study reported that women who claimed to experience vaginal orgasm were statistically more likely to have thicker tissue in the anterior vaginal wall. 

# The Skene's Glands
Other researchers have attempted to locate the G-spot by building on the claim that G-spot stimulation leads to female ejaculation. Tepper hypothesized that non-urine female ejaculate originated from the female paraurethral glands, or Skene's gland. In their study they examined tissue from 18 patients and demonstrated that 15 showed prostate-specific antigens.
More recent studies have backed up this finding, leading some to call the Skene's glands the female prostate. This finding has been used to claim that the G-spot is actually a system of glands and ducts that surround the urethra. This system is located within the anterior (front) wall of the vagina, about one centimeter from the surface and one third to one-half the way in from the vaginal opening.
In July 2002, Emmanuele Jannini of the University of Aquila, Italy discovered PDE5 activity in the area of the G-spot and speculated that the absence of G-spot orgasms is connected to the lack of Skene's glands in some women. In such women, concentrations of PDE5 were much lower.
However, most researchers feel that the connection between the Skene's Gland and the G-spot is weak. The Skene's Gland does not seem to have receptors for touch stimulation and no direct evidence for its involvement has been forthcoming.
Strong evidence for the existence of the G Spot was reported by Ian Sample, science correspondent for the British newspaper The Guardian, in the Thursday February 21 2008 edition.  The following is  a quote from that newspaper article: "Doctors claim to have found the first compelling evidence that the G spot exists, but say not all women appear to have one.
Ultrasound scans revealed clear anatomical differences between women who said they experienced vaginal orgasms and a group of women who did not. The scans identified a region of thicker tissue where the G spot was rumoured to be lurking, which was not visible in the women who had never had a vaginal orgasm.
Doctors at the University of L'Aquila in Italy, where the study was conducted, say the findings make it possible for women to have a rapid test to confirm whether or not they have a G spot.
The location, and even existence, of the G spot has been hotly contested in medical circles. While doctors know that female sexual anatomy varies substantially, until now there has been no solid evidence to link those differences to a woman's sexual responses.
"For the first time, it is possible to determine by a simple, rapid and inexpensive method if a woman has a G spot or not," Dr Emmanuele Jannini told New Scientist magazine.
The G spot is only thought to affect a woman's ability to have vaginal orgasms, so if women do not have one "they can still have a normal orgasm through stimulation of the clitoris," Jannini said.

# Relation with the urethral sponge
Some claim that the urethral sponge is the same as the G-spot.