Clinical phenotype, treatment strategy and pregnancy outcome of non‐criteria obstetric antiphospholipid syndrome

Problem To illustrate the clinical features, treatment strategy, and pregnancy outcome of patients with obstetric antiphospholipid syndrome (OAPS), non‐criteria obstetric antiphospholipid syndrome (NC‐OAPS) Method of study A single‐center nested case‐control study was designed. Patients with a diagnosis of OAPS and NC‐OAPS were enrolled. The medical history, coagulation status, and antibody profile data were collected. Patients were given standard anticoagulation therapy with or without glucocorticoids (GC) and/or hydroxychloroquine (HCQ) during pregnancy and were observed for their pregnancy outcome. Results A total of 47 patients with OAPS and 120 patients with NC‐OAPS were finally included, of whom 55 patients met the clinical criteria (subgroup C) and 65 met the laboratory criteria (subgroup L). Pregnancy morbidity showed significant differences: gravida, pregnancy loss in OAPS versus NC‐OAPS. The coagulation function was not significantly different between OAPS and NC‐OAPS groups, while TT and FIB were significantly higher in the subgroup C. Thromboelastography (TEG) results showed a significantly lower ANGEL in the NC‐OAPS group, a higher ANGEL and lower EPL, LY30 in the subgroup L. No differences between groups were observed in treatment strategy. The pregnancy outcomes were not significantly different between NC‐OAPS and OAPS groups. Conclusions Clinical and laboratory differences were found between OAPS and NC‐OAPS groups in this study. Patients in different subgroups of NC‐OAPS could be identified with different clinical phenotypes. A relatively hypercoagulable status existed in the OAPS group compared to NC‐OAPS, and also in the subgroup L.