Inherited thrombophilia in women with poor aPL-related obstetric history: prevalence and outcomes. Survey of 208 cases from the European Registry on Obstetric Antiphospholipid Syndrome cohort

Aim: To analyse the prevalence and effects of inherited thrombophilic disorders (ITD) on maternal–foetal outcomes in cases of antiphospholipid antibody related to obstetric complications. Methods: Women with obstetric complaints who tested positive for aPL and with inherited thrombophilia were prospectively and retrospectively included. Results: ITD data were available in 208 of 338: 147 had obstetric antiphospholipid syndrome (OAPS) and 61 aPL-related obstetric morbidity (OMAPS). 24.1% had ITD. Laboratory categories I and IIa were more related to OAPS-ITD and IIb and IIc to OMAPS-ITD. No significant differences in obstetric complaints were observed. Regarding ITD carriers, treatment rates were higher in OAPS than in OMAPS for LMWH and LDA plus LMWH (P=.002). Conclusion: Cases with aPL-related OAPS/OMAPS showed no differences in maternal–foetal outcomes regardless of the presence of one ITD. Maternal thrombotic risk was low, with ITD-positive cases included. Registry data concur with Sydney criteria, whereby aPL-ITD-positive patients are classified as having antiphospholipid syndrome.