Use of Antithrombotic Agents During Pregnancy: Antiphospholipid Antibodies
The management of these patients is problematic because few large clinical trials evaluating therapy have been performed. Regimens that have been evaluated include aspirin alone or in combination with prednisone or unfractionated heparin, and IV 7-globulin. A relatively large placebo-controlled, randomized, level I trial has recently been published and shows no benefit to the use of aspirin and prednisone in pregnant women with prior pregnancy losses and one or more autoantibodies; approximately 94 of 202 women (40%) had APLA read more canadian health&care mall. Two recent randomized, level 1 trials compared aspirin and heparin to aspirin alone and showed improved fetal survival with heparin and aspirin. These trials suggest that aspirin with heparin is the regimen of choice for the prevention of pregnancy loss in pregnant women with APLA and multiple previous pregnancy losses.
Based on current evidence, women with APLA and a history of multiple pregnancy losses are candidates for heparin plus aspirin. Pregnant women with APLA, no pregnancy losses, and previous venous thrombosis should also be considered to be candidates for heparin therapy. Women with APLA and no previous venous thrombosis and no pregnancy losses should be considered to have an increased risk of VTE and should be managed either with low-dose heparin therapy or clinical surveillance for VTE.
Safety of Aspirin During Pregnancy
Potential complications of aspirin during pregnancy include birth defects and bleeding in the neonate and in the mother. The results of a level I meta-analysis and a large (over 9,000 patients) randomized level I trial reported that low-dose (60 to 150 mg/d) aspirin therapy administered during the second and third trimesters of pregnancy in women at risk for pregnancy-induced hypertension or intrauterine growth retardation was safe for the mother and fetus because no increase in maternal or neonatal adverse effects occurred in individuals treated with aspirin. Thus, based on current evidence, low-dose aspirin (<150 mg/d) during the second and third trimesters appears to be safe, but the safety of higher doses of aspirin and/or aspirin ingestion during the first trimester remains a subject of debate.