P-TS-2 - Trends and Determinants of Peripartum Blood Transfusions

Hemorrhage is the leading cause of peripartum mortality and may be increasing in some developed countries. Transfusion of blood products is critical in mitigating blood loss during delivery, but is also a well-established risk for several serious maternal complications. Trends in peripartum transfusion in the U.S., as well as which patients are at the highest risk for transfusion, remain unclear.

Study

Design/Methods: This study used a retrospective cohort design and included data from the Recipient Epidemiology and Donor Evaluation Study-IV-Pediatric (REDS-IV-P) database. REDS-IV-P is a network of community and university hospitals and blood donor centers across four U.S. regional hubs in New York, New England, Wisconsin, and California. The analytical cohort included liveborn, in-hospital deliveries between 4/1/2019 and 3/30/2024. The outcome was any peripartum (within ±7 days of delivery) blood product transfusion (red blood cells [RBC], plasma, platelet, and/or cryoprecipitate). Sociodemographic (e.g., maternal age, race/ethnicity, health insurance) and medical-obstetric exposures (e.g., gestational age at delivery, placenta previa, preeclampsia) were examined. Sensitivity analyses examined associations in the subset of peripartum blood transfusion cases with severe hemorrhage ( >3 RBC units received within one hour, or >10 RBC units within 24 hours).

Results/Findings:

There were 158,322 deliveries over the 5-year study, with transfusion occurring in 4,246 (2.7%). Transfusions products included RBC (n=4,116, 97%), plasma (n=584, 14%), platelets (n=353, 8%), and cryoprecipitate (n=308, 7%). Overall risk of transfusion increased, going from ~2% early in the study period to ~3% in later years (p for trend < 0.001). Multivariable analyses outlined in Figure A indicate the odds of peripartum transfusion were higher for deliveries where patients had an underlying hemoglobinopathy (OR = 3.35 [2.65, 4.24]), venous thromboembolism (OR = 3.25 [2.47, 4.26]), received hemostatic factor (OR = 10.30 [9.58, 11.06]), mechanical ventilation (OR = 13.91 [8.76, 18.96]), or hysterectomy (OR = 13.68 [9.86, 18.96]). The odds of severe hemorrhage were higher for deliveries where patients had an underlying bleeding disorder (OR = 6.91 [4.65, 10.27]) or placenta accreta (OR = 5.17 [3.72, 7.17]).

Conclusions:

Findings from the REDS-IV network suggest that peripartum transfusions (including major hemorrhage events) may be increasing in the U.S. and are driven by underlying medical-obstetric risk factors in pregnant patients, including bleeding disorders and hemoglobinopathies, among other conditions. Better access to and utilization of high-quality prenatal care is likely needed to identify pregnant patients with these identified risk factors, as they could potentially benefit from delivery planning to help prevent or mitigate the need for peripartum transfusions.