Pre-ejaculate (also known as pre-ejaculatory fluid or Cowper's fluid, and colloquially as pre-cum) is the clear, colorless, viscous fluid that emits from the urethra of a man's penis when he is sexually aroused.

Origin and composition

Pre-ejaculate on a human penis

The amount of fluid that the human male issues varies widely among individuals. Some men do not produce any pre-ejaculate fluid,^[2] while others emit as much as 5 mL.^[1]

Pre-ejaculate contains some chemicals associated with semen, such as acid phosphatase. Some semen markers, such as gamma-glutamyltransferase, are completely absent from pre-ejaculate fluid.^[3]

Function

Acidic environments are hostile to sperm. Pre-ejaculate neutralizes residual acidity in the urethra caused by urine, creating a more favorable environment for the passage of sperm. The vagina is normally acidic; the deposit of pre-ejaculate prior to the emission of semen may change the vaginal environment to promote sperm survival.^[1]

Pre-ejaculate also acts as lubricant during intercourse,^[1] and plays a role in semen coagulation.^[1]

Pre-ejaculate, a more viscous higher flow variation

Risks

Studies have demonstrated the presence of HIV in pre-ejaculate, which can lead to the disease AIDS.^[4]

Many also express concern that pre-ejaculate may contain sperm which can cause pregnancy, using this to argue against the use of coitus interruptus (withdrawal) as a contraceptive method. There have been no large-scale studies of sperm in pre-ejaculate, but some smaller-scale studies suggest that no sperm is present and thus pre-ejaculate is ineffectual at causing pregnancy.^[4][5] It is likely, however, that pre-ejaculate which follows a recent ejaculation will contain sperm, as some ejaculate is always left in the duct after orgasm.^[6]

Overproduction

A few men are bothered by the amount of pre-ejaculate fluid they produce. One physician described a patient who was embarrassed that the fluid would "soak through his pants during kissing or other mild erotic stimulation". A few case reports have indicated satisfactory results when such men are treated with a 5-alpha-reductase inhibitor.^[7]

In such cases, one doctor recommended considering the differential diagnosis of prostatorrhea, the emission of prostatic secretions during straining associated with urination or defecation.^[7]

Religious attitudes

In Sunni Islam, the emission of pre-ejaculate fluid may require ritual purification.^[8] For many other religions, pre-ejaculate is not of significance.

References

ar:??? cs:Preejakulát da:Prĉejakulat de:Lusttropfen es:Líquido preseminal fr:Liquide pré-éjaculatoire ko:??? it:Pre-eiaculazione la:Praeeiaculatum lt:Prejakuliatas hu:El?váladék nl:Voorvocht ja:????? pl:Preejakulat pt:Fluido pré-ejaculatório sv:Försats