Editing Orgasm (section)

=== Physiological responses ===

Masters and Johnson were some of the first researchers to study the sexual response cycle in the early 1960s, based on the observation of 382 women and 312 men. They describe a cycle that begins with excitement as blood rushes into the genitals, then reaches a plateau during which they are fully aroused, which leads to orgasm, and finally resolution, in which the blood leaves the genitals.<ref name="M&J" />

In the 1970s, Kaplan added the category of desire to the cycle, which she argues precedes sexual excitation. She states that emotions of anxiety, defensiveness, and the failure of communication can interfere with desire and orgasm.<ref>{{Cite journal |author = Kaplan HS |title = Hypoactive sexual desire |journal = [[Journal of Sex & Marital Therapy]] |volume = 3 |issue = 1 |pages = 3–9 |date = 1977 |pmid = 864734 |doi = 10.1080/00926237708405343 }}</ref> In the late 1980s and after, Rosemary Basson proposed a more cyclical alternative to what had largely been viewed as a linear progression.<ref>{{Cite news |first = Martin |last = Portner |title = The Orgasmic Mind: The Neurological Roots of Sexual Pleasure |date = May 15, 2008 |url = http://www.scientificamerican.com/article.cfm?id=the-orgasmic-mind |work = Scientific American |access-date = July 16, 2009 |url-status = live |archive-url = https://web.archive.org/web/20131102222534/http://www.scientificamerican.com/article.cfm?id=the-orgasmic-mind |archive-date = November 2, 2013 |df = mdy-all }}</ref> In her model, desire feeds arousal and orgasm and is in turn fueled by the rest of the orgasmic cycle. Rather than orgasm being the peak of the sexual experience, she suggests that it is just one point in the circle and that people could feel sexually satisfied at any stage, reducing the focus on climax as an end goal of all sexual activity.<ref>{{Cite journal |author = Basson R |title = The female sexual response: a different model |journal = [[Journal of Sex & Marital Therapy]] |volume = 26 |issue = 1 |pages = 51–65 |date = 2000 |pmid = 10693116 |doi = 10.1080/009262300278641 |doi-access = free }}</ref>

==== Females ====

A woman's orgasm may, in some cases, last a little longer than a man's.<ref name="Rathus" /><ref name=soc/><ref>{{Cite news |title = Women fall into 'trance' during orgasm |work = The Times |date = June 20, 2005 |url = http://www.timesonline.co.uk/tol/life_and_style/health/article535521.ece |archive-url = https://web.archive.org/web/20110715222511/http://www.timesonline.co.uk/tol/life_and_style/health/article535521.ece |archive-date = July 15, 2011 |access-date = August 6, 2012 |location = London }}</ref> Women's orgasms have been estimated to last on average approximately 20 seconds and to consist of a series of muscular contractions in the pelvic area that includes the vagina, the uterus, and the anus.<ref name="Levin">{{Cite journal |last = Levin |first = Roy J. |author2 = Gorm Wagner |author-link2 = Gorm Wagner |date = 1985 |title = Orgasm in women in the laboratory—quantitative studies on duration, intensity, latency, and vaginal blood flow |journal = Archives of Sexual Behavior |volume = 14 |issue = 5 |pages = 439–449 |doi = 10.1007/BF01542004 |pmid = 4062540 |s2cid = 6967042 }}</ref> For some women, on some occasions, these contractions begin soon after the woman reports that the orgasm has started and continue at intervals of about one second with initially increasing and then reducing intensity. In some instances, the series of regular contractions is followed by a few additional contractions or shudders at irregular intervals.<ref name="Levin" /> In other cases, the woman reports having an orgasm, but no pelvic contractions are measured at all.<ref>{{Cite journal |last = Bohlen |first = Joseph G. |author2 = James P. Held |author3 = Margaret Olwen Sanderson |author4 = Andrew Ahlgren |title = The female orgasm: Pelvic contractions |journal = Archives of Sexual Behavior |date = 1982 |pages = 367–386 |volume = 11 |issue = 5 |doi = 10.1007/BF01541570 |pmid = 7181645 |s2cid = 33863189 }}</ref>

Women's orgasms are preceded by the erection of the clitoris and moistening of the opening of the vagina. Some women exhibit a [[sex flush]], a reddening of the skin over much of the body due to increased blood flow to the skin. As a woman nears orgasm, the clitoral glans retracts under the clitoral hood, and the [[labia minora]] (inner lips) become darker. As orgasm becomes imminent, the outer third of the vagina tightens and narrows, while overall the vagina lengthens and dilates and also becomes congested from engorged soft tissue.<ref>{{cite web |title = Anatomic and physiologic changes during female sexual response |website = Clinical Proceedings |publisher = Association of Reproductive Health Professionals |url = http://www.arhp.org/healthcareproviders/cme/onlinecme/NYNCP/changes.cfm |archive-url = https://web.archive.org/web/20080708005232/http://www.arhp.org/healthcareproviders/cme/onlinecme/NYNCP/changes.cfm |archive-date = July 8, 2008 |access-date = February 1, 2007 }}</ref>

Elsewhere in the body, [[myofibroblast]]s of the nipple-[[Areolar connective tissue|areolar]] complex contract, causing erection of the nipples and contraction of the areolar diameter, reaching their maximum at the start of orgasm.<ref>{{cite journal |journal = [[Sexual and Relationship Therapy]] |volume = 21 |issue = 1 |pages = 237–249 |title = The Breast/Nipple/Areola Complex and Human Sexuality |date = May 2, 2006 |last = Levin |first = Roy |quote = Areola corrugation immediately after orgasm physically signals that orgasm has occurred |doi = 10.1080/14681990600674674 |s2cid = 219696836 |df = mdy-all }}</ref> A woman experiences full orgasm when her uterus, vagina, anus, and pelvic muscles undergo a series of rhythmic contractions. Most women find these contractions very pleasurable.

Researchers from the [[University of Groningen|University Medical Center of Groningen]] in the [[Netherlands]] correlated the sensation of orgasm with muscular contractions occurring at a frequency of 8–13&nbsp;Hz centered in the pelvis and measured in the anus. They argue that the presence of this particular frequency of contractions can distinguish between voluntary contraction of these muscles and spontaneous involuntary contractions, and appears to more accurately correlate with orgasm as opposed to other metrics like heart rate that only measure excitation. They assert that they have identified "[t]he first objective and quantitative measure that has a strong correspondence with the subjective experience that orgasm ultimately is" and state that the measure of contractions that occur at a frequency of 8–13&nbsp;Hz is specific to orgasm. They found that using this metric they could distinguish between rest, voluntary muscular contractions, and even unsuccessful orgasm attempts.<ref name = "Kortekaas 2008">{{Cite journal |vauthors = van Netten JJ, Georgiadis JR, Nieuwenburg A, Kortekaas R |title = 8–13 Hz fluctuations in rectal pressure are an objective marker of clitorally-induced orgasm in women |journal = Archives of Sexual Behavior |volume = 37 |issue = 2 |pages = 279–85 |date = April 2008 |pmid = 17186125 |doi = 10.1007/s10508-006-9112-9 |s2cid = 17498707 |url = https://eprints.qut.edu.au/93254/1/Van%20Netten%20Georgiadis%20ms_aseb-06-50.pdf |access-date = May 29, 2020 |archive-date = September 18, 2020 |archive-url = https://web.archive.org/web/20200918023850/https://eprints.qut.edu.au/93254/1/Van%20Netten%20Georgiadis%20ms_aseb-06-50.pdf |url-status = live }}</ref>

Since ancient times in Western Europe, women could be [[Medical diagnosis|medically diagnosed]] with a disorder called [[female hysteria]], the symptoms of which included faintness, nervousness, insomnia, fluid retention, heaviness in abdomen, muscle spasm, shortness of breath, irritability, loss of appetite for food or sex, and "a tendency to cause trouble".<ref name=Maines>{{cite book |author = Maines, Rachel P. |title = The Technology of Orgasm: "Hysteria", the Vibrator, and Women's Sexual Satisfaction |publisher = The Johns Hopkins University Press |location = Baltimore |date = 1998 |isbn = 978-0-8018-6646-3 }}</ref> Women considered to have the condition would sometimes undergo "pelvic massage:" stimulation of the genitals by the doctor until the woman experienced "hysterical paroxysm" (i.e., orgasm). Paroxysm was regarded as a medical treatment and not a sexual release.<ref name=Maines/> The disorder has ceased to be recognized as a medical condition since the 1920s.

==== Males ====

As a man nears orgasm during stimulation of the penis, he feels an intense and highly pleasurable pulsating sensation of [[Neuromuscular junction|neuromuscular]] [[euphoria]]. These pulsating sensations originate from the contractions of pelvic floor muscles that begin in the anal sphincter and travel to the tip of the penis, commonly described as a "throbbing" or "tingling" sensation. They eventually increase in speed and intensity as the orgasm approaches, until a final "plateau" (the orgasmic) pleasure is sustained for several seconds.<ref name="Dunn" />

During orgasm a male experiences rapid, rhythmic contractions of the [[Human anus|anal sphincter]], the prostate, and the [[bulbospongiosus muscle]]s of the penis. The [[sperm]] are transmitted up the [[vasa deferentia]] from the [[testicles]], into the prostate gland as well as through the [[seminal vesicle]]s to produce what is known as [[semen]].<ref name="Dunn" /> The prostate produces a secretion that forms one of the components of ejaculate. Except for in cases of a dry orgasm, contraction of the sphincter and prostate force stored semen to be expelled through [[External urethral orifice (male)|the penis's urethral opening]]. The process takes from three to ten seconds and produces a pleasurable feeling.<ref name="Mah" /><ref name="Dunn" /> Ejaculation may continue for a few seconds after the euphoric sensation gradually tapers off. It is believed that the feeling of "orgasm" varies from one man to another.<ref name="Mah" />  After ejaculation, a refractory period usually occurs, during which a man cannot achieve another orgasm. This can last anywhere from less than a minute to several hours or days, depending on age and other individual factors.<ref name="soc" /><ref name="Schacter" /><ref name="Weiner & Craighead" />