Vas deferens
Human male reproductive system
Vertical section of the testis, to show the arrangement of the ducts.
Details
Precursor	Wolffian duct
Identifiers
MeSH	D014649
TA	A09.3.05.001
FMA	19234
Anatomical terminology [edit on Wikidata]

The vas deferens (or ductus deferens) ^[1] is a duct in a man’s body. It is also present in other male vertebrates. Its function is to carry sperm away from the testes, towards the penis.

There are two of these ducts, which are tubes surrounded by smooth muscle. They connect the left and right epididymis to the ejaculatory ducts in order to move sperm. Each tube is about 30 centimeters long. During ejaculation the smooth muscle in the wall of the vas deferens contracts. That pushes the sperm toward the penis. The sperm go from the vas deferens into the urethra. Other male sex glands push out at the same time.

There is a surgery called vasectomy that is a method of contraception. The two vasa deferentia (Latin plural) are cut and sealed, so the sperm cannot get out of the body. This is usually permanent, but in some cases, it can be reversed. Sometimes instead of cutting the vas deferentia, the surgeon puts something to block the sperm instead of cutting them.

• Cystic fibrosis

Human reproductive system
Female anatomy	Female reproductive system – Breasts – Cervix – Clitoris – Clitoral hood – Fallopian tubes – Bartholin's glands – Gräfenberg spot (G-spot) – Hymen – Labia – Ovaries – Skene's glands – Urethra – Uterus – Vagina – Vulva
Female physiology	Menstruation – Pregnancy – Childbirth – Lactation – Estrogen – Orgasm – Ovum
Male anatomy	Male reproductive system – Bulbourethral glands – Corpus cavernosum – Ejaculatory ducts – Epididymis – Foreskin – Frenulum – Glans penis – Penis – Prostate – Rete testis – Scrotum – Seminal vesicles – Seminiferous tubules – Sertoli cell – Spermatic cord – Testicles (testes) – Urethra – Vasa deferentia
Male physiology	Ejaculation – Erection – Orgasm – Semen – Sperm – Testosterone
Anatomy is the study of the parts of the body • Physiology is the study of how the body works