The manifestations of antiphospholipid antibodies in pregnancy are multiple and include maternal arterial and venous thrombosis, spontaneous abortion, intrauterine fetal death, intrauterine growth retardation, and preeclampsia. Maternal complications may also arise in the puerperium with the development of an autoimmune pleuropulmonary postpartum syndrome. Currently, there is confusion in the literature regarding appropriate treatment of patients known to possess these antibodies. We have reported the case of a patient at 29 weeks' gestation who had elevated blood pressure, proteinuria, and early intrauterine growth retardation. Studies were positive for the presence of both lupus anticoagulant and anticardiolipin antibodies. After delivery, chest pain and a pleural effusion developed as further manifestations of the patient's autoimmune disease.