Thromboembolic risk in pregnant women with SARS-CoV-2 infection - A systematic review

The infection by SARS-CoV-2 is associated with a thromboembolic complications risk theoretically increased. Pregnancy, isolated, is considered a pro-thrombotic state. This systematic review has the main goal to evaluate the thromboembolic risk in pregnant women with COVID-19 disease, namely for pulmonary embolism (PE) and deep vein thrombosis (DVT). The secondary goal is the evaluation of the need for thromboprophylaxis in these cases. Three databases - PubMed, Scopus and Web of Science - were searched on October 2021, using the following Mesh terms and keywords: "(covid-19 OR SARS-CoV-2 OR Covid) AND (pregnancy) AND (coagulopathy OR blood coagulation disorders OR thrombotic complications OR thromboembolic risk OR venous thromboembolism OR venous thrombosis)". Information about thrombotic complications in pregnancy and thromboprophylaxis was collected, by two independent reviewers. In total, 12 articles were analyzed, corresponding to 18205 pregnant women with SARS- CoV-2 infection. A total of 85 cases of thromboembolic events were diagnosed (0.46%, 95% CI 0.37-0.58%), of which only 17 reported the use of thromboprophylaxis (20.00%, 95% CI 12.10-30.08%). There were 3 deaths due to thromboembolic complications (3.53%, 95% CI 0.73-9.97%). In conclusion, in pregnant women, the SARS-CoV-2 infection increases the risk of thromboembolic complications. However, the risk is not greater than in the general population. It is recommended thromboprophylaxis with low molecular weight heparin for hospitalized pregnant women, and in groups with moderate to high thromboembolic risk at home self-isolation.