
Pre-ejaculate (also known as pre-ejaculatory fluid, pre-seminal fluid or Cowper's fluid, and colloquially as pre-cum) is a clear, colorless,
viscous
Viscosity is a measure of a fluid's rate-dependent resistance to a change in shape or to movement of its neighboring portions relative to one another. For liquids, it corresponds to the informal concept of ''thickness''; for example, syrup h ...
fluid that is emitted from the
urethra
The urethra (: urethras or urethrae) is the tube that connects the urinary bladder to the urinary meatus, through which Placentalia, placental mammals Urination, urinate and Ejaculation, ejaculate.
The external urethral sphincter is a striated ...
of the
penis
A penis (; : penises or penes) is a sex organ through which male and hermaphrodite animals expel semen during copulation (zoology), copulation, and through which male placental mammals and marsupials also Urination, urinate.
The term ''pen ...
during
sexual arousal
Sexual arousal (also known as sexual excitement) describes the Physiology, physiological and psychological responses in preparation for sexual intercourse or when exposed to Sexual stimulation, sexual stimuli. A number of physiological response ...
and in general during
sexual activity. It is similar in composition to
semen
Semen, also known as seminal fluid, is a bodily fluid that contains spermatozoon, spermatozoa which is secreted by the male gonads (sexual glands) and other sexual organs of male or hermaphrodite, hermaphroditic animals. In humans and placen ...
but has distinct chemical differences. The presence of
sperm
Sperm (: sperm or sperms) is the male reproductive Cell (biology), cell, or gamete, in anisogamous forms of sexual reproduction (forms in which there is a larger, female reproductive cell and a smaller, male one). Animals produce motile sperm ...
in the fluid varies from low to absent. Pre-ejaculate functions as a
lubricant
A lubricant (sometimes shortened to lube) is a substance that helps to reduce friction between surfaces in mutual contact, which ultimately reduces the heat generated when the surfaces move. It may also have the function of transmitting forces, ...
and an
acid
An acid is a molecule or ion capable of either donating a proton (i.e. Hydron, hydrogen cation, H+), known as a Brønsted–Lowry acid–base theory, Brønsted–Lowry acid, or forming a covalent bond with an electron pair, known as a Lewis ...
neutralizer.
Origin and composition
The fluid is discharged from the urethra of the penis during
arousal,
masturbation
Masturbation is a form of autoeroticism in which a person Sexual stimulation, sexually stimulates their own Sex organ, genitals for sexual arousal or other sexual pleasure, usually to the point of orgasm. Stimulation may involve the use of han ...
,
foreplay or at an early stage during
sexual intercourse
Sexual intercourse (also coitus or copulation) is a sexual activity typically involving the insertion of the Erection, erect male Human penis, penis inside the female vagina and followed by Pelvic thrust, thrusting motions for sexual pleasure ...
, some time before the individual fully reaches
orgasm
Orgasm (from Greek , ; "excitement, swelling"), sexual climax, or simply climax, is the sudden release of accumulated sexual excitement during the sexual response cycle, characterized by intense sexual pleasure resulting in rhythmic, involu ...
and semen is
ejaculated. It is primarily produced by the
bulbourethral glands (Cowper's glands), with the
glands of Littré (the mucus-secreting urethral glands) also contributing.
The amount of fluid that is issued varies widely among individuals. Some individuals do not produce any pre-ejaculate fluid, while others emit as much as .
Pre-ejaculate fluid contains chemicals associated with semen, such as
acid phosphatase, but other semen markers, such as
gamma-glutamyltransferase
Gamma-glutamyltransferase (also γ-glutamyltransferase, GGT, gamma-GT, gamma-glutamyl transpeptidase; ) is a transferase (a type of enzyme) that catalyzes the transfer of gamma- glutamyl functional groups from molecules such as glutathion ...
, are absent.
Function and risks
Pre-ejaculate neutralizes acidity in the urethra caused by residual
urine
Urine is a liquid by-product of metabolism in humans and many other animals. In placental mammals, urine flows from the Kidney (vertebrates), kidneys through the ureters to the urinary bladder and exits the urethra through the penile meatus (mal ...
, creating a more favorable environment for the passage of sperm.
[ The ]vagina
In mammals and other animals, the vagina (: vaginas or vaginae) is the elastic, muscular sex organ, reproductive organ of the female genital tract. In humans, it extends from the vulval vestibule to the cervix (neck of the uterus). The #Vag ...
is normally acidic, so the deposit of pre-ejaculate before the emission of semen may change the vaginal environment to promote sperm survival. Pre-ejaculate also acts as a lubricant during sexual activity
Human sexual activity, human sexual practice or human sexual behaviour is the manner in which humans experience and express their sexuality. People engage in a variety of sexual acts, ranging from activities done alone (e.g., masturbation) t ...
, and plays a role in semen coagulation.
Low levels or no sperm exists in pre-ejaculate, although studies examined small samples of men. Two contrary studies found mixed evidence, including individual cases of a high sperm concentration. There is evidence – dating to a 1966 Masters and Johnson study – that pre-ejaculate may contain sperm that can cause pregnancy, which is a common basis of argument against the use of coitus interruptus (withdrawal) as a contraceptive method.
Studies have demonstrated the presence of HIV in most pre-ejaculate samples from infected men.
Overproduction
In rare cases, an individual may produce an excessive amount of pre-ejaculate fluid, which may be treatable by a 5-alpha-reductase inhibitor, such as finasteride
Finasteride, sold under the brand names Proscar and Propecia among others, is a medication used to treat pattern hair loss and benign prostatic hyperplasia (BPH) in men. It can also be used to treat hirsutism, excessive hair growth in women. It ...
.
References
{{DEFAULTSORT:Pre-Ejaculate
Semen
Ejaculation
Men's health