The seminal vesicles are paired, highly coiled, tubular structures located above the prostate and behind the urinary bladder. The seminal vesicles merge with vas deferens before debouching into the urethra. The pseudostratified columnar epithelium in seminal vesicles is surrounded by thick fibromuscular tissue. The glandular epithelium is composed of columnar and basal epithelial cells. The columnar epithelium typically contains large amounts of lipofuscin pigment. An unusual feature of normal epithelial cells is the feature of cellular atypia. However, atypical cells are often encountered in the seminal vesicle epithelium, where epithelial cells with large atypical nuclei often are present.
It is within the seminal vesicles a majority of the components of semen are produced. The fluid produced in the seminal vesicle glands includes fibrinogen, prostaglandins as well as fructose and citric acid.