Lupus Anticoagulants, Anticardiolipin Antibodies, and Fetal Loss

Background. Lupus anticoagulants and anticardiolipin antibodies are antiphospholipid antibodies that have been associated with fetal loss, but they have not been shown unequivocally to be a risk factor for this event. Methods. To estimate the risk of fetal loss in association with these antibodies, we conducted a hospital-based case–control study of 331 women with spontaneous abortion or fetal death (case patients) and 993 controls. The subjects were included in the study only if they reported that they had had no previous spontaneous fetal loss. Each control was a pregnant woman who, in the same period of pregnancy as a case patient, had not had a fetal loss. Lupus anticoagulants were identified in blood samples through a series of coagulation tests, and IgG anticardiolipins by an enzyme-linked immunosorbent assay. Each subject was interviewed in person to obtain information on potential confounding variables, such as sociodemographic characteristics and medical conditions. Results. Lupus antico...