The vas deferens is part of the male reproductive system. Used to carry ejaculatory sperm out of the epididymis, the vas deferens consists of two ducts. The left and right vas deferens connect to each testicle through the epididymis.
Each vas deferens is a tube that is approximately one foot (12 inches) in length and protected by smooth muscle mass. This muscle mass contracts reflexively during ejaculation in a process called peristalsis during orgasm. This is the process that allows sperm to flow through the vas deferens and reach the urethra. On its way, the sperm collects secretions from the prostate gland, bulbourethral glands, and seminal vesicles.
During a vasectomy, a permanent male contraception method, the vas deferens are accessed through the scrotum and occluded either through ligating (tying-off) or clipping / cauterizing (burning) the vas ends.
New male contraceptive research involves the injection of material into the vas deferens to reversibly obstruct sperm flow. MCI Grantee Contraline has advanced their method to testing in men, and other methods of vas-occlusive contraception are in development. Further testing to ensure that these new methods of vasectomy are safe and reversible is ongoing.
Read more about the vas-occlusive male birth control devices Male Contraceptive Initiative is supporting on our Grantees page.
Nuts & Bolts: Vas Deferens
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For additional terminology related to male contraception and the male reproductive system, please visit our glossary:
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