Recurrent pregnancy loss is secondary to multiple illnesses. An important cause sometimes undiagnosed is the antiphospholipid syndrome, an autoimmune disease with various clinical alterations (miscarriage, hypertensive disorders, preterm delivery, vascular thrombosis, intrauterine retard growth, death intrauterine, abruption placentae). There are major and minor clinical criteria and precise indications that guide the physician to its recognition. Antibodies related with the syndrome are anticardiolipin and lupic anticoagulant, but other phospholipids seems to be implicated on this pathology and its participation on trombotic events is even unknown. Opportune diagnosis is of vital importance for fetomaternal morbidity and mortality. The repercussions are important during gestational stage, but effects c an persist o r even appear during the puerperium, predisposing t o trombotic events. The antiphospholipid s yndrome th at accompanies gestation, requires of efficient valuation and a special treatment, with a narrow prenatal surveillance. The best therapy for reproductive future which has less undesirable effects, is with heparin and acetylsalicylic acid administration; prednisone (steroids) is used in cases of active illness. The current knowledge about this disease makes possible that a pregnancy at term can be achieved with the least as possible number of complications.