Primary thromboprophylaxis for asymptomatic people with persistent high-risk aPL-antibody profiles, who are thromboembolism-free and trying to conceive

Asymptomatic people with persistent high-risk aPL-antibody profiles (as determined by a specialist) do not have a diagnosis of antiphospholipid syndrome; however, they are at increased risk of pregnancy-related thromboembolism and obstetric complications. All asymptomatic people with high-risk aPL-antibody profiles should receive contraceptive advice and prepregnancy assessment and counselling, because of their high risk.

If people with high-risk aPL-antibody profiles are trying to conceive, primary thromboprophylaxis with low-dose aspirin is recommended in most circumstancesSammaritano, Bermas, 2020Tektonidou, 2019; the usual regimen is:

If the person becomes pregnant, continue low-dose aspirin ideally throughout pregnancy. Refer to a specialist obstetrician or obstetric physician for ongoing management.

In situations associated with a high risk of developing VTE (eg gynaecological or obstetric surgery, the peri- or postpartum periods, prolonged immobilisation), people with high-risk aPL-antibody profiles should receive appropriate thromboprophylaxis (eg with LMW heparin). The appropriate regimen depends on the person’s risk factor(s). For details on thromboprophylaxis regimens in various situations, see VTE prophylaxis.