Delusion of fetal duplication in a Capgras patient.

A case of Capgras syndrome in a pregnant patient is described. In addition to perceiving living family members as impostors, she believed that there was a double or twin of her fetus. She conceptualized her "twins" differently than the way she viewed doubles of family members. Her fetus may represent the youngest "person" to have been duplicated. The relationship of Capgras syndrome to misidentification phenomena is discussed.