The =internal iliac= or =hypogastric veins= (Vv. hypogastricæ), right
and left, are usually formed by the confluence of lateral sacral,
gluteal, and internal pudic veins. The obturator vein may open into them
also. They are short trunks and are smaller than the external iliac
veins. The tributaries correspond in general to the branches of the
three arteries of like names. The internal pudic veins receive affluents
from the venous plexuses of the prepuce and penis in the male; of the
mammary gland, vulva, vagina, and vestibular bulb in the female.