Acute optic disc edema is a recently recognized, relatively benign manifestation of juvenile-onset diabetes mellitus. Twenty-three cases have been reported in the ophthalmology literature, two occurring during pregnancy. The authors present an additional case recognized in a pregnant patient and review the literature. The disorder manifests physical findings similar to those of papilledema, proliferative retinopathy with optic disc edema, inflammatory papillitis, and ischemic optic neuropathy, but has a benign course that requires no treatment and is not adversely affected by pregnancy. It is important to recognize this syndrome because failure to make the correct diagnosis in pregnancy may lead to inappropriate treatment, including therapeutic abortion. © 1984 The American College of Obstetricians and Gynecologists.