Antiphospholipid antibodies induce several obstetric complications including recurrent spontaneous abortion, preterm birth, intrauterine fetal death. EULAR recommendations for antiphospholipid syndrome (APS) indicates low dose aspirin (LDA) and/or low weight molecule heparin (LWMH) as a conventional therapy for APS¹⁾. However, Pregnant women with antiphospholipid antibodies sometimes had adverse pregnancy outcomes (APOs) under the appropriate conventional treatment. We hereby investigated the risk factors for APOs in the patients with antiphospholipid antibodies under the conventional therapies.

We retrospectively examined 28 patients who were positive for antiphospholipid antibodies and treated with conventional therapies (LDA and/or LWMH). They were managed from planning for pregnancy to delivery in our institution. We analyzed whether history of obstetric complications, types or numbers of positive auto-antibodies, and treatment agents except for APS during pregnancy influenced on APOs (including spontaneous abortion, stillbirth, preterm birth, low birth weight, and preeclampsia).

Fifty-three cases (28.5%) of all 186 pregnancies cases complicated with connective tissue disease was positive for antiphospholipid. Patients characteristics in this study was shown in Table 1. Twenty-eight cases (52.8%) were treated with conventional therapies (LDA and/or LWMH).  As for the type of CTD complicated, nine cases (32.1%) were systemic lupus erythematosus. The type of antiphospholipid antibodies was as followed; presence of triple antiphospholipid antibodies was 6 cases, double was 1 case, single was 21 cases. Eleven cases (39.3%) were treated with both LDA and LWMH, and the others were treated with either of them. APOs occurred in 11 cases (45.8%), which excluded 2 cases of induced abortion. In the group which had occurred APOs, the rate of positive for lupus anticoagulant (LAC) was significantly higher than the other group (P< 0.05, Table 2). In addition, the frequency of glucocorticoid use and mean glucocorticoid dose was also significant higher (Both of them was P< 0.01) in patients with APOs. However, there was no significance focusd on history of obstetric and thrombotic complications, the number of positive auto-antibodies, treatment regimen for APS such as LDA and/or LWMH.

In our study, LAC positivity, glucocorticoid use and mean glucocorticoid administration during pregnancy amount is associated with the development of APO in antiphospholipid antibody-positive pregnant patients under conventional treatment.  It was shown that there was no significant difference in the development of APOs between LDA + LWMH, LDA alone and LWMH alone. Treatment with at least one or more anticoagulant drugs reduced APO development in women with positive antiphospholipid antibodies. Additionally, in other treatments, it is needed to note the risk of glucocorticoid use for APOs in CTD patients with APS.