Schwannomas arc benign nerve sheath tumors that may originate at any a
natomic site. Usually they are found on the peripheral nerves of the h
ead, neck or flexor surfaces of the upper extremities. Rarely does a s
chwannoma originate in the pelvis and present as a retroperitoneal pel
vic mass, Only two previous cases of a pelvic schwannoma complicating
pregnancy have been presented in the English-language literature. We p
resent a third case.