Location Two primary methods have been used to define and locate the G-spot as a sensitive area in the
vagina: self-reported levels of arousal during stimulation, and stimulation of the G-spot leading to female ejaculation. The location of the G-spot is typically reported as being about inside the vagina, on the front wall. For some women, stimulating this area creates a more intense orgasm than clitoral stimulation. Attempting to stimulate the area through
sexual penetration, especially in the
missionary position, is difficult because of the particular angle of penetration required. Women usually need direct
clitoral stimulation in order to orgasm, and G-spot stimulation may be best achieved by using both
manual stimulation and vaginal penetration.
Sex toys are available for G-spot stimulation. One common sex toy is the specially designed
G-spot vibrator, which is a
phallic vibrator that has a curved tip and attempts to make G-spot stimulation easy. G-spot vibrators are made from the same materials as regular vibrators, ranging from hard plastic, rubber,
silicone,
jelly, or any combination of them. Another study, in 1983, examined eleven women by
palpating the entire vagina in a clockwise fashion, and reported a specific response to stimulation of the anterior vaginal wall in four of the women, concluding that the area is the G-spot. In a 1990 study, an anonymous questionnaire was distributed to 2,350 professional women in the United States and Canada with a subsequent 55% return rate. Of these respondents, 40% reported having a fluid release (ejaculation) at the moment of orgasm, and 82% of the women who reported the sensitive area (Gräfenberg spot) also reported ejaculation with their orgasms. Several variables were associated with this perceived existence of female ejaculation. Some research suggests that G-spot and clitoral orgasms are of the same origin.
Masters and Johnson were the first to determine that the clitoral structures surround and extend along and within the labia. Upon studying women's
sexual response cycle to different stimulation, they observed that both clitoral and vaginal orgasms had the same stages of physical response, and found that the majority of their subjects could only achieve clitoral orgasms, while a minority achieved vaginal orgasms. On this basis, Masters and Johnson argued that clitoral stimulation is the source of both kinds of orgasms, reasoning that the clitoris is stimulated during penetration by friction against its hood. Researchers at the
University of L'Aquila, using ultrasonography, presented evidence that women who experience vaginal orgasms are statistically more likely to have thicker tissue in the anterior vaginal wall. Professor of
genetic epidemiology, Tim Spector, who co-authored research questioning the existence of the G-spot and finalized it in 2009, also hypothesizes thicker tissue in the G-spot area; he states that this tissue may be part of the clitoris and is not a separate erogenous zone. Supporting Spector's conclusion is a study published in 2005 which investigates the size of the clitoris – it suggests that clitoral tissue extends into the anterior wall of the vagina. The main researcher of the studies, Australian
urologist Helen O'Connell, asserts that this interconnected relationship is the physiological explanation for the conjectured G-spot and experience of vaginal orgasms, taking into account the stimulation of the internal parts of the clitoris during vaginal penetration. While using
MRI technology, O'Connell noted a direct relationship between the legs or roots of the clitoris and the erectile tissue of the "clitoral bulbs" and corpora, and the distal urethra and vagina. "The vaginal wall is, in fact, the clitoris," said O'Connell. "If you lift the skin off the vagina on the side walls, you get the bulbs of the clitoris – triangular, crescental masses of erectile tissue." In their 2009 published study, the "coronal planes during perineal contraction and finger penetration demonstrated a close relationship between the root of the clitoris and the anterior vaginal wall". Buisson and Foldès suggested "that the special sensitivity of the lower anterior vaginal wall could be explained by pressure and movement of clitoris's root during a vaginal penetration and subsequent perineal contraction". it has been unofficially called the male G-spot because it can also
be used as an erogenous zone.
Regnier de Graaf, in 1672, observed that the secretions (female ejaculation) by the erogenous zone in the vagina lubricate "in agreeable fashion during coitus". Modern scientific hypotheses linking G-spot sensitivity with female ejaculation led to the idea that non-urine female ejaculate may originate from the Skene's gland, with the Skene's gland and male prostate acting similarly in terms of prostate-specific antigen and prostate-specific
acid phosphatase studies, which led to a trend of calling the Skene's glands the female prostate. Because of these factors, it has been argued that the G-spot is a system of
glands and
ducts located within the anterior (front) wall of the vagina. ==Clinical significance==