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Ejaculation

January 13, 2023

This article is about male ejaculation. For the female counterpart, see Female ejaculation. For other uses, see Ejaculation (disambiguation).

Ejaculation is the discharge of semen (the ejaculate; normally containing sperm) from the male reproductory tract as a result of an orgasm. It is the final stage and natural objective of male sexual stimulation, and an essential component of natural conception. In rare cases, ejaculation occurs because of prostatic disease. Ejaculation may also occur spontaneously during sleep (a nocturnal emission or "wet dream"). Anejaculation is the condition of being unable to ejaculate. Ejaculation is usually very pleasurable for men; dysejaculation is an ejaculation that is painful or uncomfortable. Retrograde ejaculation is the condition where semen travels backwards into the bladder rather than out the urethra.

Ejaculation example
Look up ejaculate in Wiktionary, the free dictionary.

Phases

Stimulation

See also: Sexual stimulation, Orgasm § In males, Intravaginal ejaculation latency time, and Sexual arousal § Male physiological response

A usual precursor to ejaculation is the sexual arousal of the male, leading to the erection of the penis, though not every arousal nor erection leads to ejaculation. Penile sexual stimulation during masturbation or vaginal, anal, oral, or non-penetrative sexual activity may provide the necessary stimulus for a man to achieve orgasm and ejaculation. With regard to intravaginal ejaculation latency time, men typically reach orgasm 5–7 minutes after the start of penile-vaginal intercourse, taking into account their desires and those of their partners, but 10 minutes is also a common intravaginal ejaculation latency time.[1][2] A prolonged stimulation either through foreplay (kissing, petting and direct stimulation of erogenous zones before penetration during intercourse) or stroking (during masturbation) leads to an adequate amount of arousal and production of pre-ejaculatory fluid. While the presence of sperm in pre-ejaculatory fluid is thought to be rare, sperm from an earlier ejaculation, still present in the urethra, may be picked up by pre-ejaculatory fluid.[citation needed] In addition, infectious agents (including HIV) can often be present in pre-ejaculate.

Premature ejaculation is when ejaculation occurs before the desired time. If a man is unable to ejaculate in a timely manner after prolonged sexual stimulation, in spite of his desire to do so, it is called delayed ejaculation or anorgasmia. An orgasm that is not accompanied by ejaculation is known as a dry orgasm.

Video of an ejaculation

When a man has achieved a sufficient stimulation and orgasm, ejaculation begins. At that point, under the control of the sympathetic nervous system, semen containing sperm is produced (emission).[3] The semen is ejected through the urethra with rhythmic contractions.[4] These rhythmic contractions are part of the male orgasm. They are generated by the bulbospongiosus and pubococcygeus muscles[5] under the control of a spinal reflex at the level of the spinal nerves S2–4 via the pudendal nerve. The typical male orgasm lasts several seconds.

After the start of orgasm, pulses of semen begin to flow from the urethra, reach a peak discharge and then diminish in flow. The typical orgasm consists of 10 to 15 contractions, although the man is unlikely to be consciously aware of that many. Once the first contraction has taken place, ejaculation will continue to completion as an involuntary process. At this stage, ejaculation cannot be stopped. The rate of contractions gradually slows during the orgasm. Initial contractions occur at an average interval of 0.6 seconds with an increasing increment of 0.1 seconds per contraction. Contractions of most men proceed at regular rhythmic intervals for the duration of the orgasm. Many men also experience additional irregular contractions at the conclusion of the orgasm.[6]

Ejaculation usually begins during the first or second contraction of orgasm. For most men, the first ejection of semen occurs during the second contraction, while the second is typically the largest expelling 40% or more of total semen discharge. After this peak, the magnitude of semen the penis emits diminishes as the contractions begin to lessen in intensity. The muscle contractions of the orgasm can continue after ejaculation with no additional semen discharge occurring. A small sample study of seven men showed an average of 7 spurts of semen followed by an average of 10 more contractions with no semen expelled. This study also found a high correlation between number of spurts of semen and total ejaculate volume, i.e., larger semen volumes resulted from additional pulses of semen rather than larger individual spurts.[7]

Alfred Kinsey measured the distance of ejaculation, in "some hundreds" of men. In three-quarters of men tested, ejaculate "is propelled with so little force that the liquid is not carried more than a minute distance beyond the tip of the penis." In contrast to those test subjects, Kinsey noted "In other males the semen may be propelled from a matter of some inches to a foot or two, or even as far as five or six and (rarely) eight feet".[8] Masters and Johnson report ejaculation distance to be no greater than 30–60 cm (12–24 in).[9] During the series of contractions that accompany ejaculation, semen is propelled from the urethra at 500 cm/s (200 in/s), close to 18 km/h (11 mph).[5]

Refractory period

Most men experience a refractory period immediately following an orgasm, during which time they are unable to achieve another erection, and a longer period again before they are capable of achieving another ejaculation. During this time a male feels a deep and often pleasurable sense of relaxation, usually felt in the groin and thighs. The duration of the refractory period varies considerably, even for a given individual. Age affects the recovery time, with younger men typically recovering faster than older men, though not universally so.[9]

Whereas some men may have refractory periods of 15 minutes or more, some men are able to experience sexual arousal immediately after ejaculation. A short recovery period may allow partners to continue sexual play relatively uninterrupted by ejaculation. Some men may experience their penis becoming hypersensitive to stimulation after ejaculation, which can make sexual stimulation unpleasant even while they may be sexually aroused.

There are men who are able to achieve multiple orgasms, with or without the typical sequence of ejaculation and refractory period. Some of those men report not noticing refractory periods, or are able to maintain erection by "sustaining sexual activity with a full erection until they passed their refractory time for orgasm when they proceeded to have a second or third orgasm".[10]

Volume

The force and amount of semen that will be ejected during an ejaculation will vary widely between men and may contain between 0.1 and 10 milliliters[11] (by way of comparison, note that a teaspoon is 5 ml and a tablespoon holds 15 ml). Adult semen volume is affected by the time that has passed since the previous ejaculation; larger semen volumes are seen with greater durations of abstinence. The duration of the stimulation leading up to the ejaculation can affect the volume.[12] Abnormally low semen volume is known as hypospermia and abnormally high semen volume is known as hyperspermia. One of the possible underlying causes of low volume or complete lack of semen is ejaculatory duct obstruction. It is normal for the amount of semen to diminish with age.

Quality

Main article: Semen quality

The number of sperm in an ejaculation also varies widely, depending on many factors, including the time since the last ejaculation,[13] age, stress levels,[14] and testosterone. Greater lengths of sexual stimulation immediately preceding ejaculation can result in higher concentrations of sperm.[12] An unusually low sperm count, not the same as low semen volume, is known as oligospermia, and the absence of any sperm from the semen is termed azoospermia.

Development

During puberty

 
Diagram of the male pelvic and reproductive organs
See also: Spermarche

The first ejaculation in males often occurs about 12 months after the onset of puberty, generally through masturbation or nocturnal emission (wet dreams). This first semen volume is small. The typical ejaculation over the following three months produces less than 1 ml of semen. The semen produced during early puberty is also typically clear. After ejaculation this early semen remains jellylike and, unlike semen from mature males, fails to liquefy. A summary of semen development is shown in Table 1.

Most first ejaculations (90%) lack sperm. Of the few early ejaculations that do contain sperm, the majority of sperm (97%) lack motion. The remaining sperm (3%) have abnormal motion.[15]

As the male proceeds through puberty, the semen develops mature characteristics with increasing quantities of normal sperm. Semen produced 12 to 14 months after the first ejaculation liquefies after a short period of time. Within 24 months of the first ejaculation, the semen volume and the quantity and characteristics of the sperm match that of adult male semen.[15]

Semen development during puberty
Time after first
ejaculation (months) 		Average volume
(milliliter) 		Liquefaction Average sperm concentration
(million sperm/milliliter)
0 0.5 Noa 0
6 1.0 Noa 20
12 2.5 No/Yesb 50
18 3.0 Yesc 70
24 3.5 Yesc 300

^a Ejaculate is jellylike and fails to liquefy.
^b Most samples liquefy. Some remain jellylike.
^c Ejaculate liquefies within an hour.

Control from the central nervous system

There is a central pattern generator in the spinal cord, made up of groups of spinal interneurons, that is involved in the rhythmic response of ejaculation. This is known as the spinal generator for ejaculation.[16]

To map the neuronal activation of the brain during the ejaculatory response, researchers have studied the expression of c-Fos, a proto-oncogene expressed in neurons in response to stimulation by hormones and neurotransmitters.[17] Expression of c-Fos in the following areas has been observed:[18][19]

Hands-free ejaculation

Although uncommon, some men can achieve ejaculations during masturbation without any manual stimulation. Such men usually do it by tensing and flexing their abdominal and buttocks muscles along with vigorous fantasising. Others may do it by relaxing the area around the penis, which may result in harder erections especially when hyperaroused.[20]

Perineum pressing and retrograde ejaculation

Perineum pressing results in an ejaculation which is purposefully held back by pressing on either the perineum or the urethra to force the seminal fluid to remain inside. In such a scenario, the seminal fluid stays inside the body and goes to the bladder. Some people do this to avoid making a mess by keeping all the semen inside.[21] As a medical condition, it is called retrograde ejaculation.[22]

Health issues

For most men, no detrimental health effects have been determined from ejaculation itself or from frequent ejaculations,[citation needed] though sexual activity in general can have health or psychological consequences. A small fraction of men have a disease called postorgasmic illness syndrome (POIS), which causes severe muscle pain throughout the body and other symptoms immediately following ejaculation. The symptoms last for up to a week.[23][24][25] Some doctors speculate that the frequency of POIS "in the population may be greater than has been reported in the academic literature",[26] and that many POIS sufferers are undiagnosed.[27]

It is not clear whether frequent ejaculation has any effect on the risk of prostate cancer.[28][29][30] Two large studies examining the issue were[31][32][33] "Ejaculation Frequency and Subsequent Risk of Prostate Cancer"[34] and "Sexual Factors and Prostate Cancer".[35] These suggest that frequent ejaculation after puberty offers some reduction of the risk of prostate cancer. The US study involving 29,342 US men aged 46 to 81 years[34] suggested that "high ejaculation frequency was related to decreased risk of total prostate cancer".[34] An Australian study involving 1,079 men with prostate cancer and 1,259 healthy men found that "there is evidence that the more frequently men ejaculate between the ages of 20 and 50, the less likely they are to develop prostate cancer":

[T]he protective effect of ejaculation is greatest when men in their twenties ejaculated on average seven or more times a week. This group were one-third less likely to develop aggressive prostate cancer when compared with men who ejaculated less than three times a week at this age.[36]

Other animals

See also: Semen collection § By species

In mammals and birds, multiple ejaculation is commonplace.[37][38][clarification needed] During copulation, the two sides of a short-beaked echidna's penis are used sequentially. Alternating between the two sides allows for persistent stimulation to induce ejaculation without impeding the refractory period.[39]

In stallions, ejaculation is accompanied by a motion of the tail known as "tail flagging".[40] When a male wolf ejaculates, his final pelvic thrust may be slightly prolonged.[41] A male rhesus monkey usually ejaculates less than 15 seconds after sexual penetration.[42] The first report and footage of spontaneous ejaculation in an aquatic mammal was recorded in a wild Indo-Pacific bottlenose dolphin near Mikura Island, Japan, in 2012.[43]

In horses, sheep, and cattle, ejaculation occurs within a few seconds, but in boars, it can last for five to thirty[44] minutes.[45] Ejaculation in boars is stimulated when the spiral-shaped penis interlocks with the female's cervix.[46] A mature boar can produce 250–300 ml (8.8–10.6 imp fl oz; 8.5–10.1 US fl oz) of semen during one ejaculation.[45] In llamas and alpacas, ejaculation occurs continuously during copulation.[47]

The semen of male dogs is ejaculated in three separate phases.[48] The last phase of a male canine’s ejaculation occurs during the copulatory tie, and contains mostly prostatic fluid.[49]

See also

References

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Further reading

 
Wikimedia Commons has media related to Male ejaculation.
  • . Focus on Fertility, American Infertility Association and Organon Pharmaceuticals USA Inc. 2017-08-21. Archived from the original on 2008-01-12.
  • Glover, Tim (30 June 2012). Mating Males: An Evolutionary Perspective on Mammalian Reproduction. Cambridge University Press. pp. 105–. ISBN 978-1-107-00001-8. Retrieved 28 May 2013.
  • Smith, Robert L. (28 December 1984). Sperm Competition and the Evolution of Animal Mating systems. Elsevier. ISBN 978-0-323-14313-4. Retrieved 28 May 2013.
  • Gray, Peter B. (1 April 2013). Evolution and Human Sexual Behavior. Harvard University Press. pp. 9–. ISBN 978-0-674-07437-8. Retrieved 28 May 2013.
  • Breed, Michael D.; Moore, Janice (2010). Encyclopedia of Animal Behavior. Elsevier. ISBN 978-0-08-045336-1. Retrieved 28 May 2013.

January 13, 2023
ejaculation, this, article, about, male, ejaculation, female, counterpart, female, ejaculation, other, uses, disambiguation, discharge, semen, ejaculate, normally, containing, sperm, from, male, reproductory, tract, result, orgasm, final, stage, natural, objec. This article is about male ejaculation For the female counterpart see Female ejaculation For other uses see Ejaculation disambiguation Ejaculation is the discharge of semen the ejaculate normally containing sperm from the male reproductory tract as a result of an orgasm It is the final stage and natural objective of male sexual stimulation and an essential component of natural conception In rare cases ejaculation occurs because of prostatic disease Ejaculation may also occur spontaneously during sleep a nocturnal emission or wet dream Anejaculation is the condition of being unable to ejaculate Ejaculation is usually very pleasurable for men dysejaculation is an ejaculation that is painful or uncomfortable Retrograde ejaculation is the condition where semen travels backwards into the bladder rather than out the urethra Ejaculation example Look up ejaculate in Wiktionary the free dictionary Contents 1 Phases 1 1 Stimulation 1 2 Refractory period 1 3 Volume 1 4 Quality 2 Development 2 1 During puberty 2 2 Control from the central nervous system 2 3 Hands free ejaculation 2 4 Perineum pressing and retrograde ejaculation 3 Health issues 4 Other animals 5 See also 6 References 7 Further readingPhasesStimulation See also Sexual stimulation Orgasm In males Intravaginal ejaculation latency time and Sexual arousal Male physiological response A usual precursor to ejaculation is the sexual arousal of the male leading to the erection of the penis though not every arousal nor erection leads to ejaculation Penile sexual stimulation during masturbation or vaginal anal oral or non penetrative sexual activity may provide the necessary stimulus for a man to achieve orgasm and ejaculation With regard to intravaginal ejaculation latency time men typically reach orgasm 5 7 minutes after the start of penile vaginal intercourse taking into account their desires and those of their partners but 10 minutes is also a common intravaginal ejaculation latency time 1 2 A prolonged stimulation either through foreplay kissing petting and direct stimulation of erogenous zones before penetration during intercourse or stroking during masturbation leads to an adequate amount of arousal and production of pre ejaculatory fluid While the presence of sperm in pre ejaculatory fluid is thought to be rare sperm from an earlier ejaculation still present in the urethra may be picked up by pre ejaculatory fluid citation needed In addition infectious agents including HIV can often be present in pre ejaculate Premature ejaculation is when ejaculation occurs before the desired time If a man is unable to ejaculate in a timely manner after prolonged sexual stimulation in spite of his desire to do so it is called delayed ejaculation or anorgasmia An orgasm that is not accompanied by ejaculation is known as a dry orgasm source source source source source source source source source track Video of an ejaculation When a man has achieved a sufficient stimulation and orgasm ejaculation begins At that point under the control of the sympathetic nervous system semen containing sperm is produced emission 3 The semen is ejected through the urethra with rhythmic contractions 4 These rhythmic contractions are part of the male orgasm They are generated by the bulbospongiosus and pubococcygeus muscles 5 under the control of a spinal reflex at the level of the spinal nerves S2 4 via the pudendal nerve The typical male orgasm lasts several seconds After the start of orgasm pulses of semen begin to flow from the urethra reach a peak discharge and then diminish in flow The typical orgasm consists of 10 to 15 contractions although the man is unlikely to be consciously aware of that many Once the first contraction has taken place ejaculation will continue to completion as an involuntary process At this stage ejaculation cannot be stopped The rate of contractions gradually slows during the orgasm Initial contractions occur at an average interval of 0 6 seconds with an increasing increment of 0 1 seconds per contraction Contractions of most men proceed at regular rhythmic intervals for the duration of the orgasm Many men also experience additional irregular contractions at the conclusion of the orgasm 6 Ejaculation usually begins during the first or second contraction of orgasm For most men the first ejection of semen occurs during the second contraction while the second is typically the largest expelling 40 or more of total semen discharge After this peak the magnitude of semen the penis emits diminishes as the contractions begin to lessen in intensity The muscle contractions of the orgasm can continue after ejaculation with no additional semen discharge occurring A small sample study of seven men showed an average of 7 spurts of semen followed by an average of 10 more contractions with no semen expelled This study also found a high correlation between number of spurts of semen and total ejaculate volume i e larger semen volumes resulted from additional pulses of semen rather than larger individual spurts 7 Alfred Kinsey measured the distance of ejaculation in some hundreds of men In three quarters of men tested ejaculate is propelled with so little force that the liquid is not carried more than a minute distance beyond the tip of the penis In contrast to those test subjects Kinsey noted In other males the semen may be propelled from a matter of some inches to a foot or two or even as far as five or six and rarely eight feet 8 Masters and Johnson report ejaculation distance to be no greater than 30 60 cm 12 24 in 9 During the series of contractions that accompany ejaculation semen is propelled from the urethra at 500 cm s 200 in s close to 18 km h 11 mph 5 Refractory period Most men experience a refractory period immediately following an orgasm during which time they are unable to achieve another erection and a longer period again before they are capable of achieving another ejaculation During this time a male feels a deep and often pleasurable sense of relaxation usually felt in the groin and thighs The duration of the refractory period varies considerably even for a given individual Age affects the recovery time with younger men typically recovering faster than older men though not universally so 9 Whereas some men may have refractory periods of 15 minutes or more some men are able to experience sexual arousal immediately after ejaculation A short recovery period may allow partners to continue sexual play relatively uninterrupted by ejaculation Some men may experience their penis becoming hypersensitive to stimulation after ejaculation which can make sexual stimulation unpleasant even while they may be sexually aroused There are men who are able to achieve multiple orgasms with or without the typical sequence of ejaculation and refractory period Some of those men report not noticing refractory periods or are able to maintain erection by sustaining sexual activity with a full erection until they passed their refractory time for orgasm when they proceeded to have a second or third orgasm 10 Volume The force and amount of semen that will be ejected during an ejaculation will vary widely between men and may contain between 0 1 and 10 milliliters 11 by way of comparison note that a teaspoon is 5 ml and a tablespoon holds 15 ml Adult semen volume is affected by the time that has passed since the previous ejaculation larger semen volumes are seen with greater durations of abstinence The duration of the stimulation leading up to the ejaculation can affect the volume 12 Abnormally low semen volume is known as hypospermia and abnormally high semen volume is known as hyperspermia One of the possible underlying causes of low volume or complete lack of semen is ejaculatory duct obstruction It is normal for the amount of semen to diminish with age Quality Main article Semen quality The number of sperm in an ejaculation also varies widely depending on many factors including the time since the last ejaculation 13 age stress levels 14 and testosterone Greater lengths of sexual stimulation immediately preceding ejaculation can result in higher concentrations of sperm 12 An unusually low sperm count not the same as low semen volume is known as oligospermia and the absence of any sperm from the semen is termed azoospermia DevelopmentDuring puberty Diagram of the male pelvic and reproductive organs See also Spermarche The first ejaculation in males often occurs about 12 months after the onset of puberty generally through masturbation or nocturnal emission wet dreams This first semen volume is small The typical ejaculation over the following three months produces less than 1 ml of semen The semen produced during early puberty is also typically clear After ejaculation this early semen remains jellylike and unlike semen from mature males fails to liquefy A summary of semen development is shown in Table 1 Most first ejaculations 90 lack sperm Of the few early ejaculations that do contain sperm the majority of sperm 97 lack motion The remaining sperm 3 have abnormal motion 15 As the male proceeds through puberty the semen develops mature characteristics with increasing quantities of normal sperm Semen produced 12 to 14 months after the first ejaculation liquefies after a short period of time Within 24 months of the first ejaculation the semen volume and the quantity and characteristics of the sperm match that of adult male semen 15 Semen development during puberty Time after first ejaculation months Average volume milliliter Liquefaction Average sperm concentration million sperm milliliter 0 0 5 Noa 06 1 0 Noa 2012 2 5 No Yesb 5018 3 0 Yesc 7024 3 5 Yesc 300 a Ejaculate is jellylike and fails to liquefy b Most samples liquefy Some remain jellylike c Ejaculate liquefies within an hour Control from the central nervous system There is a central pattern generator in the spinal cord made up of groups of spinal interneurons that is involved in the rhythmic response of ejaculation This is known as the spinal generator for ejaculation 16 To map the neuronal activation of the brain during the ejaculatory response researchers have studied the expression of c Fos a proto oncogene expressed in neurons in response to stimulation by hormones and neurotransmitters 17 Expression of c Fos in the following areas has been observed 18 19 medial preoptic area MPOA lateral septum bed nucleus of the stria terminalis paraventricular nucleus of hypothalamus PVN ventromedial nucleus of the hypothalamus medial amygdala ventral premammillary nuclei ventral tegmental area central tegmental field mesencephalic central gray peripeduncular nuclei parvocellular subparafascicular nucleus SPF within the posterior thalamusHands free ejaculation Although uncommon some men can achieve ejaculations during masturbation without any manual stimulation Such men usually do it by tensing and flexing their abdominal and buttocks muscles along with vigorous fantasising Others may do it by relaxing the area around the penis which may result in harder erections especially when hyperaroused 20 Perineum pressing and retrograde ejaculation Perineum pressing results in an ejaculation which is purposefully held back by pressing on either the perineum or the urethra to force the seminal fluid to remain inside In such a scenario the seminal fluid stays inside the body and goes to the bladder Some people do this to avoid making a mess by keeping all the semen inside 21 As a medical condition it is called retrograde ejaculation 22 Health issuesFor most men no detrimental health effects have been determined from ejaculation itself or from frequent ejaculations citation needed though sexual activity in general can have health or psychological consequences A small fraction of men have a disease called postorgasmic illness syndrome POIS which causes severe muscle pain throughout the body and other symptoms immediately following ejaculation The symptoms last for up to a week 23 24 25 Some doctors speculate that the frequency of POIS in the population may be greater than has been reported in the academic literature 26 and that many POIS sufferers are undiagnosed 27 It is not clear whether frequent ejaculation has any effect on the risk of prostate cancer 28 29 30 Two large studies examining the issue were 31 32 33 Ejaculation Frequency and Subsequent Risk of Prostate Cancer 34 and Sexual Factors and Prostate Cancer 35 These suggest that frequent ejaculation after puberty offers some reduction of the risk of prostate cancer The US study involving 29 342 US men aged 46 to 81 years 34 suggested that high ejaculation frequency was related to decreased risk of total prostate cancer 34 An Australian study involving 1 079 men with prostate cancer and 1 259 healthy men found that there is evidence that the more frequently men ejaculate between the ages of 20 and 50 the less likely they are to develop prostate cancer T he protective effect of ejaculation is greatest when men in their twenties ejaculated on average seven or more times a week This group were one third less likely to develop aggressive prostate cancer when compared with men who ejaculated less than three times a week at this age 36 Other animalsSee also Semen collection By species In mammals and birds multiple ejaculation is commonplace 37 38 clarification needed During copulation the two sides of a short beaked echidna s penis are used sequentially Alternating between the two sides allows for persistent stimulation to induce ejaculation without impeding the refractory period 39 In stallions ejaculation is accompanied by a motion of the tail known as tail flagging 40 When a male wolf ejaculates his final pelvic thrust may be slightly prolonged 41 A male rhesus monkey usually ejaculates less than 15 seconds after sexual penetration 42 The first report and footage of spontaneous ejaculation in an aquatic mammal was recorded in a wild Indo Pacific bottlenose dolphin near Mikura Island Japan in 2012 43 In horses sheep and cattle ejaculation occurs within a few seconds but in boars it can last for five to thirty 44 minutes 45 Ejaculation in boars is stimulated when the spiral shaped penis interlocks with the female s cervix 46 A mature boar can produce 250 300 ml 8 8 10 6 imp fl oz 8 5 10 1 US fl oz of semen during one ejaculation 45 In llamas and alpacas ejaculation occurs continuously during copulation 47 The semen of male dogs is ejaculated in three separate phases 48 The last phase of a male canine s ejaculation occurs during the copulatory tie and contains mostly prostatic fluid 49 See also Human sexuality portalAspermia Coitus interruptus Coitus reservatus Cum shot Facial sexual act Fertilisation Hematospermia Insemination Sperm donation Spermatorrhea TesticleReferences Waldinger M D Quinn P Dilleen M Mundayat R Schweitzer D H Boolell M 2005 A Multinational Population Survey of Intravaginal Ejaculation Latency Time Journal of Sexual Medicine 2 4 492 497 doi 10 1111 j 1743 6109 2005 00070 x PMID 16422843 Giuliano F Patrick D Porst R La Pera G Kokoszka A Merchant S Rothman M Gagnon D Polverejan E 2008 Premature Ejaculation Results from a Five Country European Observational Study European Urology 53 5 1048 1057 doi 10 1016 j eururo 2007 10 015 PMID 17950985 Koeppen Bruce M Stanton Bruce A 2008 Berne amp Levy Physiology Philadelphia PA Elsevier Mosby ISBN 978 0 323 04582 7 Boron Walter F Boulpaep Emile L 2005 Medical Physiology A Cellular and Molecular Approach Philadelphia PA Elsevier Saunders ISBN 978 1 4160 2328 9 a b Marieb Elaine 2013 Anatomy amp physiology Benjamin Cummings p 895 ISBN 978 0 321 88760 3 Bolen J G 1980 12 09 The male orgasm pelvic contractions measured by anal probe Archives of Sexual Behavior 9 6 503 21 doi 10 1007 BF01542155 PMID 7458658 S2CID 32523063 Gerstenburg T C Levin RJ Wagner G 1990 Erection and ejaculation in man Assessment of the electromyographic activity of the bulbocavernosus and ischiocavernosus muscles British Journal of Urology 65 4 395 402 doi 10 1111 j 1464 410X 1990 tb14764 x PMID 2340374 Kinsey A C Pomeroy W B Martin C E Gebhard P H 1998 Sexual Behavior in the Human Female Indiana University Press p 634 ISBN 978 0 253 33411 4 Retrieved 2013 11 07 a b Masters W H Johnson V E 1970 Human Sexual Response Boston Little Brown and Company Dunn M E Trost J E 1989 Male Multiple Orgasms A Descriptive Study Archives of Sexual Behavior 18 5 377 387 doi 10 1007 BF01541970 PMID 2818169 S2CID 13647953 Rehan N Sobrero A J Fertig J W 1975 The semen of fertile men statistical analysis of 1300 men Fertility and Sterility 26 6 492 502 doi 10 1016 s0015 0282 16 41169 6 PMID 1169171 a b Pound N Javed M H Ruberto C Shaikh M A Del Valle A P 2002 Duration of sexual arousal predicts semen parameters for masturbatory ejaculates Physiol Behav 76 4 5 685 9 doi 10 1016 S0031 9384 02 00803 X PMID 12127009 S2CID 37524348 Semen and sperm quality Dr John Dean netdoctor co uk 2015 05 29 Archived from the original on 2009 02 28 Retrieved 2009 03 04 Biological Basis of Heredity Cell Reproduction Dr Dennis O Neil Behavioral Sciences Department Palomar College San Marcos California Retrieved 2021 01 31 a b Janczewski Z Bablok L 1985 Semen Characteristics in Pubertal Boys Archives of Andrology 15 2 3 199 205 doi 10 3109 01485018508986912 PMID 3833078 Guertin PA 2012 Central pattern generator for locomotion anatomical physiological and pathophysiological considerations Frontiers in Neurology 3 183 doi 10 3389 fneur 2012 00183 PMC 3567435 PMID 23403923 Sagar S M et al 1988 Expression of c fos protein in brain metabolic mapping at the cellular level Science 240 4857 1328 1332 Bibcode 1988Sci 240 1328S doi 10 1126 science 3131879 PMID 3131879 Pfaus J G Heeb M M 1997 Implications of immediate early gene induction in the brain following sexual stimulation of female and male rodents Brain Res Bull 44 4 397 407 doi 10 1016 S0361 9230 97 00219 0 PMID 9370204 S2CID 15435196 Veening J G Coolen L M 1998 Neural activation following sexual behavior in the male and female rat brain Behav Brain Res 92 2 181 193 doi 10 1016 S0166 4328 97 00190 3 PMID 9638960 S2CID 38940946 The Rough Guide to Sex retrieved February 2012 65 Gateway to Sexual Adventure For Women and Men Herb Hirata 2012 Andrology Male Reproductive Health and Dysfunction Page 317 E Nieschlag Hermann M Behre Susan Nieschlag 2010 Balon R Segraves RT ed 2005 Handbook of Sexual Dysfunction Taylor amp Francis ISBN 978 0 8247 5826 4 Wylie KR ed 2015 ABC of Sexual Health John Wiley amp Sons p 75 ISBN 978 1 118 66556 5 Retrieved 2015 10 21 Postorgasmic illness syndrome Genetic and Rare Diseases Information Center GARD National Institutes of Health 2015 Archived from the original on 5 March 2016 Retrieved 30 July 2015 Ashby J Goldmeier D May 2010 Postorgasm illness syndrome a spectrum of illnesses J Sex Med 7 5 1976 81 doi 10 1111 j 1743 6109 2010 01707 x PMID 20214722 McMahon CG October 2014 Post Orgasmic Illness Syndrome PDF 16th World Meeting on Sexual Medicine Dimitropoulou Polyxeni Lophatananon Artitaya Easton Douglas Pocock Richard Dearnaley David P Guy Michelle Edwards Steven O Brien Lynne Hall Amanda Wilkinson Rosemary Eeles Rosalind Muir Kenneth R November 11 2008 Sexual activity and prostate cancer risk in men diagnosed at a younger age BJU International 103 2 178 185 doi 10 1111 j 1464 410X 2008 08030 x PMID 19016689 S2CID 6339070 Masturbation Cuts Cancer Risk BBC News Online 2003 07 16 Retrieved 2009 03 04 Giles G G Severi G English D R Hopper J L 2004 Frequency of ejaculation and risk of prostate cancer JAMA 292 3 329 doi 10 1001 jama 292 3 329 a PMID 15265846 Leitzmann M F Platz E A Stampfer M J Willett W C Giovannucci E 2004 Ejaculation frequency and subsequent risk of prostate cancer JAMA 291 13 1578 86 doi 10 1001 jama 291 13 1578 PMID 15069045 Garnick Marc 24 February 2011 Does frequent ejaculation help ward off prostate cancer Harvard Medical School Prostate Knowledge Harvard University Archived from the original on 6 September 2012 Retrieved 9 February 2013 Masturbation cuts cancer risk BBC News BBC 16 July 2003 Retrieved 9 February 2013 Bhattacharya Shaoni 6 April 2004 Frequent ejaculation may protect against cancer New Scientist UK Reed Business Information Retrieved 9 February 2013 a b c Leitzmann MD Michael F Platz Elizabeth A ScD Stampfer Meir J MD Willett Walter C MD Giovannucci Edward MD 7 April 2004 Ejaculation Frequency and Subsequent Risk of Prostate Cancer Journal of the American Medical Association 291 13 1578 86 doi 10 1001 jama 291 13 1578 PMID 15069045 Giles Graham G BSc MSc PhD Severi G English D R McCredie M R Borland R Boyle P Hopper J L August 2003 Sexual factors and prostate cancer BJU International 92 3 211 16 doi 10 1046 j 1464 410X 2003 04319 x PMID 12887469 S2CID 29430415 New findings on prostate cancer risk and sexual activity Cancer Council Victoria website Cancer Council Victoria 17 July 2003 Retrieved 9 February 2013 Smith Robert L 28 December 1984 Sperm Competition and the Evolution of Animal Mating systems Elsevier ISBN 978 0 323 14313 4 Retrieved 19 April 2013 P Michael Conn 22 October 2013 Paradigms for the Study of Behavior Elsevier Science ISBN 978 1 4832 6937 5 Johnston S D Smith B Pyne M Stenzel D Holt W V 2007 One Sided Ejaculation of Echidna Sperm Bundles Tachyglossus aculeatus PDF Am Nat 170 6 E162 E164 doi 10 1086 522847 PMID 18171162 S2CID 40632746 Samper Juan C Ph D Pycock Jonatjhan F McKinnon Angus O 2007 Current therapy in equine reproduction Elsevier Health Sciences ISBN 978 0 7216 0252 3 Retrieved 18 April 2013 Mech L David Boitani Luigi 1 October 2010 Wolves Behavior Ecology and Conservation University of Chicago Press pp 44 ISBN 978 0 226 51698 1 Retrieved 19 April 2013 The pursuit of pleasure Transaction Publishers 1992 ISBN 978 1 4128 3867 2 Retrieved 19 April 2013 Morisaka Tadamichi Sakai Mai Kogi Kazunobu Nakasuji Akane Sakakibara Kasumi Kasanuki Yuria Yoshioka Motoi Sakamoto Kentaro Q 27 August 2013 Spontaneous Ejaculation in a Wild Indo Pacific Bottlenose Dolphin Tursiops aduncus PLOS ONE 8 8 e72879 Bibcode 2013PLoSO 872879M doi 10 1371 journal pone 0072879 PMC 3755988 PMID 24015280 Sergi Bonet Isabel Casas William V Holt Marc Yeste 1 February 2013 Boar Reproduction Fundamentals and New Biotechnological Trends Springer Science amp Business Media ISBN 978 3 642 35049 8 a b Heriberto Rodriguez Martinez 1 April 2010 Control of Pig Reproduction VIII Nottingham University Press pp 15 ISBN 978 1 907284 53 3 Bonnie S Dunbar M G O Rand 29 June 2013 A Comparative Overview of Mammalian Fertilization Springer Science amp Business Media ISBN 978 1 4757 8982 9 Chris Cebra David E Anderson Ahmed Tibary Robert J Van Saun LaRue Willard Johnson 15 February 2014 Llama and Alpaca Care Medicine Surgery Reproduction Nutrition and Herd Health Elsevier Health Sciences ISBN 978 0 323 24291 2 Margaret V Root Kustritz 2006 The Dog Breeder s Guide to Successful Breeding and Health Management Elsevier Health Sciences ISBN 978 1 4160 3139 0 Retrieved 2015 10 21 Edward C Feldman Richard William Nelson 2004 Canine and Feline Endocrinology and Reproduction Elsevier Health Sciences ISBN 978 0 7216 9315 6 Retrieved 2015 10 21 Further reading Wikimedia Commons has media related to Male ejaculation Swimming Toward Conception The Semen Analysis Focus on Fertility American Infertility Association and Organon Pharmaceuticals USA Inc 2017 08 21 Archived from the original on 2008 01 12 Glover Tim 30 June 2012 Mating Males An Evolutionary Perspective on Mammalian Reproduction Cambridge University Press pp 105 ISBN 978 1 107 00001 8 Retrieved 28 May 2013 Smith Robert L 28 December 1984 Sperm Competition and the Evolution of Animal Mating systems Elsevier ISBN 978 0 323 14313 4 Retrieved 28 May 2013 Gray Peter B 1 April 2013 Evolution and Human Sexual Behavior Harvard University Press pp 9 ISBN 978 0 674 07437 8 Retrieved 28 May 2013 Breed Michael D Moore Janice 2010 Encyclopedia of Animal Behavior Elsevier ISBN 978 0 08 045336 1 Retrieved 28 May 2013 Retrieved from https en wikipedia org w index php title Ejaculation amp oldid 1113975891, wikipedia, wiki, book, books, library,

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