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In addition to the vaginal passage and its surrounding labia, the female genitals also boast four sexual 'Hot Spots'. These are small zones of heightened erotic sensitivity, the stimulation of which during the mating act helps to bring the female nearer to an orgasmic condition. They are: the Clitoris, the U-spot, the G-spot, and the A-spot. The first two are outside the vagina, the second two inside it:
The Clitoris. This is the best known of the female genital hot spots, located at the top of the vulva, where the inner labia join at their upper ends. The visible part is the small, nipple-sized, female equivalent of the tip of the male penis, and is partially covered by a protective hood. Essentially it is a bundle of 8000 nerve fibres, making it the most sensitive spot on the entire female body. It is purely sexual in function and becomes enlarged (longer, more swollen, more erect) and even more sensitive during copulation. During foreplay it is often stimulated directly by touch, and many women who do not easily reach orgasm purely from vaginal stimulation find it easier to climax from oral, digital, or mechanical stimulation of the clitoris.
An Australian surgeon recently reported that the clitoris is larger than previously thought, much of it being hidden beneath the surface. The part that is visible is simply its tip, the rest of its length – its shaft – lying beneath the surface and extending down to surround the vaginal opening. This means that, during pelvic thrusting, its concealed part will be massaged vigorously by the movements of the inserted penis. There will therefore always be some degree of clitoral stimulation, even when the tip is not touched directly. The clitoral shaft is, however, less sensitive than the exposed tip, so that direct contact with the tip will always have a greater impact on female arousal. Some women claim that, by employing a rhythmic, downward roll of the pelvis, they can create a direct friction on the clitoris tip while the male is making pelvic thrusts, and can in this way magnify their arousal, but this requires a more dominant role for the female, which is not always accepted by the male.
The U-Spot. This is a small patch of sensitive erectile tissue located just above and on either side of the urethral opening. It is absent just below the urethra, in the small area between the urethra and the vagina. Less well known than the clitoris, its erotic potential was only recently investigated by American clinical research workers. They found that if this region was gently caressed, with the finger, the tongue, or the tip of the penis, there was an unexpectedly powerful erotic response.
While on the subject of the female urethra, it is important to mention 'female ejaculation'. In the male, the urethral tube delivers both urine and seminal fluid containing sperm. In the female it is usually believed that it delivers only urine, but this is not the case. When there is an unusually powerful orgasm, some females may emit a liquid from their urethral openings that is not urine. There are specialized glands surrounding the urethral tube, called Skene's glands, or para-urethral glands, similar to the male's prostate, and under extreme stimulation they produce an alkaline liquid that is chemically similar to male seminal fluid. Women who experience ejaculation (which ranges in quantity from a few drops to a few tablespoonfuls), sometimes imagine that the extreme muscular exertions of their climactic moments have forced them into involuntary urination, but this is simply because they do not understand their own physiology. Nor, incidentally, did some medical authorities, who insisted that ejaculating women were suffering from 'urinary stress incontinence' and suggested operations to cure it. (One man recently sued for divorce because he believed that his wife was urinating on him, such is the ignorance of female genital activity.)
It is not clear what the value of this female ejaculation can be, as its occurrence is clearly a little late to act as an aid to lubrication. Vaginal lubrication is, in fact, carried out by the walls of the vagina themselves, which rapidly become covered in a liquid film when female sexual arousal first begins.
The G-Spot, or Grafenberg Spot. This is a small, highly sensitive area located 5-8 cm (2-3 inches) inside the vagina, on the front or upper wall. Named after its discoverer, a German gynaecologist called Ernst Grafenberg, it is sometimes romantically referred to as the Goddess Spot. Research into the nature of the female orgasm, carried out in the 1940s, led to the discovery that the female's urethral tube, that lies on top of the vagina, is surrounded by erectile tissue similar to that found in the male penis. When the female becomes sexually aroused, this tissue starts to swell. In the G-spot zone this expansion rebults in a small patch of the vaginal wall protruding into the vaginal canal. It is this raised patch that is, according to Grafenberg, 'a primary erotic zone, perhaps more important than the clitoris'. He explains that its significance was lost when the 'missionary position' became a dominant feature of human sexual behaviour. Other sexual positions are far more efficient at stimulating this erogenous zone and therefore at achieving vaginal orgasms.
It should be pointed out that the term 'G-spot' was not used by Grafenberg himself. As mentioned above, he called it 'an erotic zone', which is a much better description of it. Unfortunately, the modern use of 'G-spot' as a popular term has led to some misunderstanding. Some women have been led to believe, optimistically. that there is a 'sex button' that can be pressed like a starter button, at any time, to cause an erotic explosion. Disappointed, they then come to the conclusion that the whole concept of a 'G-spot' is false and that it does not exist. The truth, as already explained, is that the G-spot is a sexually sensitive patch of vaginal wall that protrudes slightly only when the glands surrounding the urethral tube have become swollen. Several leading gynaecologists denied its existence when it was first discussed at their conferences, and a major controversy arose, but later, when it was specially demonstrated for their benefit, they changed their minds. Sexual politics also entered the debate, when certain anti-male campaigners rejected out of hand the idea that vaginal orgasm could be possible. For them clitoral orgasm was politically correct and no other would do. How they have reacted to the recent marketing of 'G-spotter' attachments for vibrators is not recorded.
Astonishingly, there have been recent reports that some women have been undergoing 'G-spot enhancement'. This involves injecting collagen into the G-spot zone to enlarge it. According to one source, 'One of the latest procedures to catch on is G-spot injection. Similar substances to those injected into the lips to plump them up can now be injected into your G-spot. The idea is that this will increase its sensitivity and so give you better orgasms.' This sounds more like an urban myth than a surgical reality, but where female sexual improvements are concerned, almost anything is possible.
The A-Spot, AFE-zone or Anterior Fornix Erogenous Zone. Also referred to as the Epicentre, this is a patch of sensitive tissue at the inner end of the vaginal tube between the cervix and the bladder, described technically as the 'female degenerated prostate'. (In other words, it is the female equivalent of the male prostate, just as the clitoris is the female equivalent of the male penis.) Direct stimulation of this spot can produce violent orgasmic contractions. Unlike the clitoris, it is not supposed to suffer from post-orgasmic over-sensitivity.
Its existence was reported by a Malaysian physician in Kuala Lumpur as recently as the 1990s. There has been some mis-reporting about it, and its precise position has been incorrectly described by several writers. Its true location is just above the cervix, at the innermost point of the vagina. The cervix of the uterus is the narrow part that protrudes slightly into the vagina, leaving a circular recess around itself. The front part of this recess is called the anterior fornix. Pressure on it produces rapid lubrication of the vagina, even in women who are not normally sexually responsive. It is now possible to buy a special AFE vibrator – long thin and upward curved at its end, to probe this zone.
Students of female sexual physiology claim (perhaps over-enthusiastically) that if these four erotic centres are stimulated in rotation, one after the other, it is possible for a woman to enjoy many orgasms in a single night. It is pointed out, however, that it takes an extremely experienced and sensitive lover to achieve this.
It has been claimed that two out of every three women fail to reach regular orgasms from simple penetrative sex. As mentioned above, most of them find that only digital or oral stimulation of the clitoris can be guaranteed to bring them to climax. This must mean that, for them, the two 'hot spots' inside the vagina are not living up to their name. The reason for this, it seems, is monotony in sexual positioning. A group of 27 couples were asked to vary their sexual positions experimentally, employing postures that would allow greater stimulation of the two vaginal 'hot spots', and it was found that three-quarters of the females involved were then able to achieve regular vaginal orgasms.