What are you Ejaculating – The Composition of the Ejaculate
Testis
The testes contributes to about 2-5% of the ejaculate. The main component is sperms which are produced in the seminiferous tubules in the testis. Men who have a reduced volume of ejaculate think they have no sperms. On the contrary their sperm count may be normal.
Seminal Vesicles
The bulk of the ejaculate, 60-65% comes from the seminal vesicles which are positioned below the bladder lateral to the vas deferens. The seminal vesicles secrete prostaglandins, proteins and fructose.
Prostate
The prostate contributes to about 25-30% of the semen volume. The main constituents of prostatic secretion include, prostate specific antigen, proteolytic enzymes and zinc.
Bulbourethral Glands
These glands contribute to less than 1% of the ejaculate. They secrete mucus and help the sperms swim in the vagina.
Thus we see that all white fluid is not sperm. The seminal plasma contributes to about 95% with sperms being less than 5%. In men where there is no ejaculate, a common cause would be Retrograde ejaculation where all the ejaculate goes into the bladder. A less common cause would be an ejaculatory duct obstruction.