Figure 1.

Uterine vascular anatomy: The uterine artery is the major vessel which provides blood to the uterus. At the surface of the uterus, the uterine artery branches into the arcuate artery. The radial artery, an offshoot of the arcuate artery, travels through the myometrium before giving off 2 branches at the myoendometrial junction: the basal artery and the spiral artery. Both the basal and spiral arteries transverse the endometrium and branch into capillary beds, but only the spiral artery reaches the luminal surface of the endometrium. The basal artery concludes at the basal surface of the endometrium.