The lumbar splanchnic nerves are splanchnic nerves that arise from the lumbar ganglia (the lumbar part of the sympathetic trunk)^[1] and travel to an adjacent plexus near the aorta. They originate from L1 and L2.^{[citation needed]} Together with fibres from the aortic plexus, they form the superior hypogastric plexus.^[1]

These nerves contain preganglionic sympathetic and general visceral afferent fibers.^{[citation needed]}

The site of synapse is found in the inferior mesenteric ganglion and the postsynaptic fibers innervate the smooth muscle and glands of the pelvic viscera and hindgut.^{[citation needed]}