Obstetrical antiphospholipid syndrome

Antiphospholipid syndrome (APS) is an autoimmune disease manifested by a thrombotic or obstetrical event in the presence of antiphospholipid antibodies. Obstetrical APS was initially described in the 1950s. Obstetrical features presently include recurrent pre-embryonic and embryonic miscarriage, fetal demise, preeclampsia, intrauterine growth restriction, and possibly placental abruption. Since the first description of obstetrical APS, researchers have unraveled some of the pathophysiology involved in the disease. At present, there are numerous antiphospholipid antibodies that can be measured in human serum, each of which requires evaluation with regard to whether an association with obstetrical events exists. Clinical trials have provided some insight into optimal treatment protocols, but to date, such trials are limited. On the basis of small, randomized trials, live birth rates of approximately 70 to 80% have been reported with the use of low-dose acetylsalicylic acid and heparin. Despite such encouraging results, ongoing pregnancies are fraught with maternal and fetal morbidity. This review will highlight the obstetrical morbidity associated with APS, discuss the limitations of the present criteria for diagnosis, appraise published treatment trials, and summarize directions for future study of obstetrical APS.