VPB1416 - Postpartum Thromboprophylaxis Following Caesarean Delivery

Background: Caesarean delivery (CD) increases the risk of venous thromboembolism (VTE) and bleeding events. Despite best practice recommendations for postpartum thromboprophylaxis following CD, heterogeneity of practice remains.

Aims: In the absence of a standardized institutional prescription algorithm, among women with CD, we aimed 1) To describe the current practice for postpartum thromboprophylaxis, and 2) To compare the incidence of postpartum VTE and bleeding events between those with and without postpartum thromboprophylaxis.

Methods: We performed a retrospective cohort study. We reviewed medical records of a simple random sample of all CD between January and December 2020. We identified factors associated with postpartum thromboprophylaxis and assessed adherence to the Society for Obstetricians and Gynaecologists of Canada (SOGC) best practice guidelines. VTE, primary and secondary major bleeding (MB), and clinically relevant nonmajor bleeding (CRNMB) events were compared among women with and without thromboprophylaxis using a two-way Chi-square or Fisher’s exact tests, as appropriate.

Results: Of 322 included patients with CD, 81 (25.2%) received postpartum anticoagulation. Body-mass index, pre-existing diabetes, hypertensive disorders, fetal growth restriction, gestational age at delivery, preterm premature rupture of membranes, prolonged antepartum hospitalization, strict bedrest, unplanned CD, peripartum infection, prior anticoagulation use (including in the antepartum period), length of stay, and hospital readmission were associated with postpartum thromboprophylaxis. In total, 68/199 (34.2%) of patients requiring postpartum thromboprophylaxis as per SOGC guidelines received anticoagulation. Low-molecular-weight heparin was chosen in 80/81 (98.8%) of participants, with a first dose given at 12.0 (interquartile range [IQR] 8.0-14.0) hours after delivery for a total of 2.0 (IQR 2.0-3) days. One patient developed a pulmonary embolism following hospital discharge. Participants receiving thromboprophylaxis had more primary MB and CNRMB events (Table 1).

Conclusion(s): Only one-third of women qualifying for postpartum thromboprophylaxis received anticoagulation. Participants who received thromboprophylaxis were also at increased risk of primary bleeding events.