Protein S deficiency and bilateral branch retinal artery occlusion.

A macular branch retinal artery occlusion developed in the right eye of a 25-year-old woman when she was 38 weeks pregnant. She subsequently presented 5 days postpartum with a branch retinal artery occlusion in her left eye. Although her initial work-up did not reveal a source for her occlusions, subsequent studies have documented a deficiency of protein S.