Introduction
Hypertensive disorders of pregnancy remain one of the leading causes of maternal and perinatal morbidity and mortality. It is estimated that preeclampsia complicates 2-8% of pregnancies,1-4 and is classically characterized by new onset of hypertension and proteinuria1-3,5 although clinical presentations may vary.6 Preeclampsia can be defined as either non-severe or severe, depending on the severity of hypertension or the presence of specific clinical or laboratory criteria (i.e. HELLP syndrome, eclampsia, etc).7-10 Preeclampsia with severe features may lead to end organ damage, including the central nervous system, cardiovascular system, coagulation, liver and kidney.11 Early-onset preeclampsia before 34 weeks’ gestation is generally associated with a more severe clinical course for the mother, as well as neonatal complications related to prematurity.12-13 Although the exact pathogenesis of preeclampsia in not fully appreciated, several clinical risk factors have been identified, such as nulliparity, previous history of preeclampsia, multifetal gestation, pregestational diabetes, chronic hypertension, renal disease, obesity, thrombophilia, systemic lupus erythematosus as well as antiphospholipid antibody syndrome.14-16
Antiphospholipid syndrome (APS) is an autoimmune, hypercoagulable state caused by the presence of antiphospholipid antibodies (aPL antibodies). aPL antibodies have been associated with a variety of obstetric complications, including recurrent pregnancy loss, and placental mediated complications, such as early-onset preeclampsia, intrauterine growth restriction, placental insufficiency, placental abruption, preterm delivery and late fetal loss.17-23
Despite the amassed body of evidence describing the association between aPL antibodies and preeclampsia, the significance of the presence of aPL antibodies in preeclamptic women with severe features has not been thoroughly elucidated. Specifically, it is unclear whether early-onset severe preeclampsia before 34 weeks gestation presents with different clinical features when associated with antiphospholipid antibodies.
Therefore, the aim of our study was to determine if the presence of aPL antibodies is associated with different maternal or neonatal clinical characteristics in those with early-onset preeclampsia who delivered prior to 34 weeks.