[Clinical characteristics and pregnancy outcomes of non-criteria obstetric antiphospholipid syndrome].

Objective: To study clinical characteristics and pregnancy outcomes under anti-coagulation therapy of non-criteria obstetric antiphospholipid syndrome. Methods: Patients suspected of obstetric antiphospholipid syndrome(OAPS) were recruited through Chinese Rheumatism Data Center from 2015 to 2019 consecutively. Patients fulfilling 2006 Sydney revised antiphospholipid syndrome criteria were classified as OAPS. Patients fulfilling definition of non-criteria OAPS(NCOAPS) by expert consensus on diagnosis and management of obstetric antiphospholipid syndrome of China were classified as NCOAPS. Clinical characteristics and laboratory results of two groups were compared. Live birth rates and pregnancy outcomes under anti-coagulation therapy were studied. Results: A total of 88 patients were enrolled, including 56 patients (63.6%) as OAPS, 32(36.4%) as NCOAPS. Live births were only reached in 16.1% (9/56) in OAPS patients and 12.5%(4/32) in NCOAPS. Fetal losses after 10 weeks of gestation and pre-eclampsia before 34 weeks were more common in OAPS group compared to NCOAPS group [78.6%(44/56) vs. 18.8%(6/32), P <0.001; 25.0%(14/56) vs. 3.1%(1/32), P =0.020, respectively]. After enrollment, 15 pregnancies were recorded in OAPS, 10 in NCOAPS, all of whom were treated with low-dose aspirin (LDA) combined with low-molecular weight heparin (LMWH). Live birth rates saw dramatic improvements compared to baseline levels in OAPS [16.1% (9/56) vs. 11/15] along with NCOAPS [12.5% (4/32) vs. 7/10]. Conclusion: Though NCOAPS and OAPS patients differ in antiphospholipid antibody spectrum and pattern of pregnancy morbidities, both groups benefit from LDA combined with LWMH treatment, as live birth rates improve. Non-criteria OAPS patients are recommended to receive anti-coagulation therapy during pregnancy.