From the lumen of the seminiferous tubules, the immotile sperm are surrounded by testicular fluid and moved to the epididymis- a coiled tube attached to the testis where newly formed sperm continue to mature. Though the epididymis does not take up much room in its tightly coiled state, it would be approximately 6 m (20 feet) long if straightened. It takes an average of 12 days for sperm to move through the coils of the epididymis, with the shortest recorded transit time in humans being one day.
Sperm enter the head of the epididymis and are moved along predominantly by the contraction of smooth muscles lining the epididymal tubes. As they are moved along the length of the epididymis, the sperm further mature and acquire the ability to move on their own. Once inside the female reproductive tract, they will use this ability to move independently toward the unfertilized egg. The most mature sperm are stored in the tail of the epididymis (the final section) until ejaculation occurs.
During ejaculation, sperm flow from the lower portion of the epididymis (which functions as a storage reservoir). They have not been activated by products from the prostate gland, and they are unable to move independently, therefore they are transported via the peristaltic action of muscle layers within the vas deferens, into the urethra, collecting secretions from the male accessory sex glands such as the seminal vesicles, prostate gland, and the bulbourethral glands, which form the bulk of semen.
Epididymis is divided into three main regions (Pic.1):
The major cell types in the epithelium are:
Complete absence of sperm in the ejaculate of a man.
Absence of sperm in the ejaculate despite normal spermatogenesis, caused by an obstruction of the genital tract.
Semen with a low concentration of sperm and is a common finding in male infertility.
A physical syndrome described by pain or burning sensation of the urethra or perineum during or following ejaculation.
The semen, which would normally be ejaculated via the urethra, is redirected to the urinary bladder.
Antibodies that bind to sperm, inhibiting their movement, stopping recognition and entry into the egg.
In the case of cryptorchidism one or both testes are absent from the scrotum. It is is the most common etiologic factor of azoospermy in the adult.
An abnormal enlargement of the pampiniform venous plexus in the scrotum.
The pathological inability to ejaculate in males, with (orgasmic) or without (anorgasmic) orgasm.
The failure to achieve a clinical pregnancy after 12 months or more of regular unprotected sexual intercourse.
Pain or burning sensation of the penis or scrotum following ejaculation.
A frustration caused by a discrepancy between a person's desired and achieved sexual activity.