After all the parasympathetics and sympathetics have successfully reached the inferior hypogastric plexus they must still find their way to their final destinations and synapse in the correct locations. Recall that both sympathetics and parasympathetics are each two neuron systems, but that the location of synapses in each of these systems is very different. Most of the sympathetic fibers reaching the inferior hypogastric plexus are postsynaptic, having synapsed within the lower lumbar or sacral portions of the sympathetic trunk prior to leaving it. Those preganglionic sympathetic fibers that reach the inferior hypogastric plexus synapse within small, diffuse ganglia within this plexus and then send out postganglionic fibers to their target organs. Parasympathetics, on the other hand, travel through the plexuses, but wait to synapse until they reach the wall of their target organ and then send out very short postganglionic fibers.
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