1. Previous thrombotic events? aspirin + LMW(H) * long-term use of low dose aspirin? YES aspirin; consider + (LMW)H * LMW(H) * LMW(H) * ; oral anticoagulants  YES  YES  YES long-term use of oral anticoagulants?  consider (LMW)H * aspirin + LMW(H) * YES  YES  NOYES Obstetric APS criteria fulfilled ? R/ in pregnancy LMW(H) * aspirin + LMW(H) * LMW(H) * R/ postpartum

2. Previous thrombotic events? aspirin + LMW(H) * long-term use of low dose aspirin? YES aspirin; consider + (LMW)H * LMW(H) * LMW(H) * ; oral anticoagulants  YES  YES  YES long-term use of oral anticoagulants?  consider (LMW)H * aspirin + LMW(H) * YES  YES  NOYES Obstetric APS criteria fulfilled ? R/ in pregnancy LMW(H) * aspirin + LMW(H) * LMW(H) * R/ postpartum

3. Obstetric history  2 losses < 10 weeks  3 consecutive losses < 10 weeks  1 loss> 10 weeks low dose aspirin + (LMW)H (prophylactic dose) 1,2 none LMWH (prophylactic dose)(LMW)H (prophylactic dose) R/ in pregnancy R/ postpartum

4. Obstetric history  2 losses < 10 weeks  3 consecutive losses < 10 weeks  1 loss> 10 weeks (LMW)H; restart oral anticoagulation R/ in pregnancy R/ postpartum Chronic use of low dose aspirinChronic use of oral anticoagulants  2 losses < 10 weeks  3 consecutive losses < 10 weeks  1 loss> 10 weeks low dose aspirin low dose aspirin + (LMW)H (prophylactic dose) 1,2 (LMW)H 1,2,3,4 low dose aspirin + (LMW)H 1,2,3,4 low dose aspirin + (LMW)H (prophylactic dose)

5. Indication for chronic anticoagulation absent present (LMW)H (prophylactic dose) + aspirin (LMW)H; restart oral anticoagulation Chronic use of low dose aspirin Chronic use of oral anticoagulants Continue low dose aspirin (LMW)H 1,2,3 Switch to oral anticoagulants is possible between 15 and 34 weeks’ gestation  3 consecutive losses < 10 weeks  1 loss> 10 weeks Add (LMW)H to low dose aspirin or low dose aspirin to (LMW)H R/ in pregnancy R/ postpartum