Editing Female ejaculation (section)

===Nature of different fluids===
Critics have maintained that ejaculation is either [[stress incontinence]] or [[vaginal lubrication]].<ref name="rodriguez"/> Research in this area has concentrated almost exclusively on attempts to prove that the ejaculate is not urine,<ref name="chalker02"/><ref>{{cite journal |author=Belzer EG |title=A review of female ejaculation and the Grafenberg spot |journal=Women Health |volume=9 |issue=1 |pages=5–16 |year=1984 |pmid=6367229 |doi= 10.1300/J013v09n01_02}}</ref> measuring substances such as [[urea]], [[creatinine]], [[prostatic acid phosphatase]] (PAP), [[prostate-specific antigen]] (PSA),<ref name="zaviacic99">{{cite web|url=http://www.doctorg.com/sexual_products/ebook_female_prostate.html |title=Zaviacic M. The human female prostate: From Vestigial Skene's Paraurethral Glands and Ducts to Woman's Functional Prostate. Slovak Academic Press, Bratislava 1999 |publisher=Doctorg.com |access-date=2011-10-30 |url-status=dead |archive-url=https://web.archive.org/web/20111028082511/http://www.doctorg.com/sexual_products/ebook_female_prostate.html |archive-date=2011-10-28 }}</ref> [[glucose]] and [[fructose]]<ref>{{cite journal |vauthors=Zaviačič M, Doležalová S, Holomáň IK, Zaviačičová A, Mikulecký M, Valer Brázdil V |title=Concentrations of Fructose in Female Ejaculate and Urine: A Comparative Biochemical Study |journal=J. Sex Res. |volume=24 |issue= 1|pages=319–25 |year=1988 |doi=10.1080/00224498809551431|pmid=22375668 }}</ref> levels. Early work was contradictory; the initial study on one woman by Addiego and colleagues, reported in 1981,<ref name="addiego"/> could not be confirmed in a subsequent study on 11 women in 1983,<ref name=goldberg>{{cite journal |author1=Goldberg, DC |author2=Whipple, B |author3=Fishkin, RE |author4=Waxman H |author5=Fink PJ |author6=Wiesberg M | year = 1983 | title = The Grafenberg Spot and female ejaculation: a review of initial hypotheses | journal = J Sex Marital Ther | volume = 9 | issue = 1 | pages = 27–37 | pmid =6686614 | doi = 10.1080/00926238308405831 }}</ref> but was confirmed in another 7 women in 1984.<ref name="belzerjsr84"/> In 1985, a different group studied 27 women and found only urine,<ref name=alzate85>{{cite journal |author=Alzate H |title=Vaginal eroticism: a replication study |journal=Arch Sex Behav |volume=14 |issue=6 |pages=529–37 |date=December 1985 |pmid=4084052 |doi= 10.1007/BF01541753|s2cid=44699346 }}</ref> suggesting that results depend critically on the methods used.{{citation needed|date=May 2012}}

A 2007 study on two women involved [[ultrasound]], [[endoscopy]], and biochemical analysis of fluid. The ejaculate was compared to pre-orgasmic urine from the same woman, and also to published data on [[male ejaculation|male ejaculate]]. In both women, higher levels of PSA, PAP, and glucose but lower levels of [[creatinine]] were found in the ejaculate than the urine. PSA levels were comparable to those in males.<ref name="wimpissinger">{{cite journal |vauthors=Wimpissinger F, Stifter K, Grin W, Stackl W |title=The female prostate revisited: perineal ultrasound and biochemical studies of female ejaculate |journal=J Sex Med |volume=4 |issue=5 |pages=1388–93; discussion 1393 |date=September 2007 |pmid=17634056 |doi=10.1111/j.1743-6109.2007.00542.x }}</ref>

Ultrasounds from a 2014 study, involving seven women who reported recurring massive fluid emission during sexual arousal, confirmed thorough bladder emptiness before stimulation, noticeable bladder filling before squirting and demonstrated that the bladder had again been emptied after squirting. Although small amounts of prostatic secretions are present in the emitted fluid, the study suggests that squirting is essentially the involuntary emission of urine during sexual activity.<ref name="Salama"/>