Round cells in semen are either WBCs or spermatids (immature sperm). These cells can be differentiated by examining a stained smear at 1000X magnification (oil immersion). A more precise identification can be achieved by detecting peroxidase activity.
Increased numbers of WBCs may indicate inflammation of the accessory glands.
An increase in spermatids indicates a problem with maturation in the epididymis. Sperm mature and develop tails in the epididymis of the testes. The maturation process begins with a primitive male germ cell, the spermatogonium. Spermatogonium differentiate into spermatocytes which then differentiate into spermatids through a process of mitosis and meiosis. The spermatids mature into spermatozoa without any further cell division.