Hematologic characteristics and coagulopathy in pregnancy with COVID-19 succeeding the first wave: a multicenter retrospective cross-sectional study

Background: Early reports have demonstrated an association of COVID-19 infection during pregnancy and postpartum period with coagulopathy and bleeding complications and indicated that pregnant people with COVID-19 are more likely to experience coagulopathy and venous thromboembolism. A recent report concerning such complications during the first wave of the pandemic was reassuring; however, no publications have evaluated these issues in the context of increased illness severity with the emergence of SARS-CoV-2 variants of concern.

Objectives: We performed a retrospective, multinational cohort study in Canada, Romania, and the United Kingdom, aiming to provide a comprehensive analysis of the hematologic test characteristics of pregnancies affected by COVID-19 after the first wave of the pandemic.

Results: Three-hundred-seventy patients were evaluated. Markers of inflammation and endothelial dysfunction were significantly elevated, in keeping with observations in the nonpregnant population. Reassuringly, despite more severe disease noted in succeeding waves of the pandemic, there was no significant evidence of COVID-19-associated coagulopathy, and overall, no association was demonstrated between isolated coagulation abnormalities and bleeding risk. Notably, fibrinogen below 2g/L was again linked with the risk of postpartum hemorrhage. Finally, venous thromboembolism risk was low but noted more frequently in those with severe illness despite thromboprophylaxis.

Conclusion: Our findings add valuable insights into the nature of hematologic test characteristics, bleeding, and thrombotic complications for those affected with COVID-19 in pregnancy, reassuring readers of the low incidence of bleeding and thrombotic complications but inviting further debate as to the degree of thromboprophylaxis that may benefit the subgroup with severe disease.