Spontaneous resolution of aneurysmal third nerve palsy.

Palsy of the third cranial nerve developed in a 33-year-old woman in her third trimester of pregnancy as a result of compression by a posterior communicating artery aneurysm. Prepartum complications forced postponement of surgical treatment. The palsy spontaneously resolved over 3 weeks after delivery by cesarean section. Repeat angiography suggested that the aneurysmal sac had shrunk. Spontaneous complete resolution of a third nerve palsy does not exclude an aneurysmal cause.