Background: Antiphospholipid syndrome (APS) is defined by the presence of antiphospholipid antibodies (aPL) with thrombosis and/or obstetric morbidity. aPL-associated thrombosis can affect the venous and arterial systems and also the microvasculature. We have an established antithrombotic management in pregnancy protocol aiming to prevent maternal thrombosis and obstetric morbidity.

Aims: To evaluate thrombotic outcomes in pregnancy and post partum among women with antiphospholipid antibodies followed in a tertiary care referral centre with a set protocol.

Methods: This is a retrospective observational study. Data were collected from the Lupus & Thrombosis units at St. Thomas’ Hospital, London, UK. Women were identified from clinic lists during 2010-2017. Women persistently positive for antiphospholipid antibodies were included if complete pregnancy outcome data were available.

Results: Five-hundred-and-twenty-one pregnancies in 374 women were included in the study. Thrombotic complications were encountered in 20 (4%) pregnancies, including 19 venous events and one arterial thrombosis. Five (25%) occurred in the first trimester, four (20%) in the second trimester, five (25%) in the third trimester. Six (30%) presented in the post-partum period (median 4.5 (range 1-12) weeks): two cases occurred at 8 weeks post-partum (after cessation of 6 weeks thromboprophylaxis) and one at 12 weeks post-partum (after 6 weeks of post-partum thromboprophylaxis). History of prior thrombosis was noted in 141 (27.1%) pregnancies, and was significantly associated with recurrent thrombosis despite anticoagulation therapy as compared to those with no prior thrombotic history (7.7% vs. 2.4%, P=0.009). Table 1 describes the 20 thrombotic cases encountered.

Conclusions: This study demonstrates that despite optimal and vigilant care, up to 4% of women with antiphospholipid antibodies developed thrombosis during the antenatal and postpartum course. Women with prior thrombotic history were identified as a high-risk group for recurrent thrombosis despite anticoagulation treatment. Further studies are warranted to better delineate the optimal strategy to reduce thrombosis rate in this subset of women.

[Table 1]

« Back to ISTH 2020 Congress

ISTH Congress Abstracts - https://abstracts.isth.org/abstract/thrombotic-outcomes-in-pregnant-women-with-antiphospholipid-antibodies-in-a-tertiary-referral-centre/