The spermatic cord is the cord-like structure in males formed by the vas deferens (ductus deferens) and surrounding tissue that runs from the deep inguinal ring down to each testicle. Its serosal covering, the tunica vaginalis, is an extension of the peritoneum that passes through the transversalis fascia. Each testicle develops in the lower thoracic and upper lumbar region and migrates into the scrotum during its descent it carries along with it vas deferens, its vessels, nerves etc. There is one on each side.