Anatomy and histology of seminal vesicles

Definition

• Paired male accessory sex glands; produce an alkaline secretion known to constitute the bulk of the ejaculate, promote sperm function, and provide an assortment of potent antibacterial factors to the male genital tract.

• Seminal vesicles develop as outpouchings of the lower mesonephric ducts.

• Coiled tubular structures are located along the posterolateral aspect of the external surface of the base of the urinary bladder, superior to the posterior surface of the prostate.

• In adult males, seminal vesicles average approximately 6 cm in length and 2 cm in width.

• The ducts of the seminal vesicles merge with the ampullary portion of the vasa deferentia on each side to form the ejaculatory ducts, which then enter the central zone of the prostate and converge at either side of the verumontanum in the prostatic sinus of the prostatic urethra.