Quick Facts
Sympathetic Contribution: Lumbar splanchnic nerves (T12-L2).
Parasympathetic Contribution: Pelvic splanchnic nerves (S2-S4).
Course: Fibers travel external to the peritoneum. The sympathetic fibers pass along the posterior abdominal wall to the hypogastric nerve, and the superior and inferior hypogastric plexuses. The parasympathetic fibers traverse the floor of the pelvis along the base of the broad ligament.
Sympathetic Supply: The sympathetic and parasympathetic fibers share territories of the reproductive organs and ducts, the inferior ureter of the pelvis, urethra, erectile tissue bodies, and glands of the perineum.
Parasympathetic Supply: The sympathetic and parasympathetic fibers share territories of the reproductive organs and ducts, the inferior ureter of the pelvis, as well as the urethra, erectile tissue bodies, and glands of the perineum.
Contributing Nerves
Lumbar (sympathetic) axons pass inferiorly along the medial, posterior abdominal wall into the superior hypogastric plexus, hypogastric nerves, and eventually into the inferior hypogastric plexus. Here they join the parasympathetic and pelvic splanchnic nerves. Those heading to reproductive organs emerge as the uterine nerves. These spread out to form the uterovaginal plexus.
The uterovaginal plexus corresponds to the prostatic plexus in males.
Course
The site of the sympathetic ganglionic synapse is not determined but it descends into the pelvis and emerges as sacral splanchnic nerves. Preganglionic parasympathetic axons emerge from the second to fourth sacral (S2—S4) spinal cord segments and form the pelvic splanchnic nerves. Both sacral and pelvic splanchnic nerves contribute to the inferior hypogastric plexus. Uterine nerves arise from the plexus and pass along the base of the broad ligament to the uterovaginal junction, at the level of the cervix. Nerves descend or ascend on both sides of the uterus between layers of the broad ligament.
Branches
Those fibers emerging from the uterovaginal plexus continue to be referred to as uterine nerves. However, at the uterovaginal junction, a subset turns superior and travel with the uterine artery. Other axons pass directly to the cervix. A final component of axons turns inferior and descend with the vaginal artery to become the vaginal nerves. The cavernous nerve of the clitoris may arise from the uterovaginal plexus or the vaginal nerves.
Supplied Structures
The ascending uterine nerves pass superiorly to the body of the uterus and portions of the uterine tubes, ovaries, and ureters. Those that continue medially innervate the cervix. Finally, the descending vaginal nerves supply the superior portion of the vagina, glands and erectile tissue bodies (bulbs) of the vestibule of the vagina and clitoris, and a portion of the urethra.
