Objective
Starting in the late 2019, the COVID-19 pandemic caused by SARS-CoV-2 infection has affected millions of people worldwide. Since then, multiple publications have described a hypercoagulable profile among patients with severe COVID-19.1 This apparent underlying hypercoagulable state is expected to be more deleterious during the immediate postpartum period when the risk for thromboembolic events is already markedly elevated than in nonpregnant individuals.2 In this study, we aimed to evaluate the coagulation profile of asymptomatic patients with COVID-19 during the immediate postpartum period by utilizing viscoelastic testing.
Study Design
This was a single center cohort study. The institutional review board committee approved the protocol, and informed consent was obtained from all participants. At our institution, universal screening for SARS-CoV-2 on admission, using polymerase chain reaction (PCR) testing of nasopharyngeal swabs, is routine. Asymptomatic patients who presented for delivery and who had a positive PCR test result were approached by research staff for inclusion. Based on the availability of research staff, a convenience sample of individuals with a negative PCR test result was used as the control group. Patients with known coagulopathies were excluded. The coagulation profiles for both groups were determined using viscoelastic testing (Quantra QPlus System, Hemosonics, LLC, Charlottesville, VA) on a 2 mL blood sample, collected from each participant.3 This device measures clotting time (which reflects the clotting factor function responsible for initial fibrin formation) and clot stiffness (which provides an independent value for the fibrinogen and platelet contribution to the overall stiffness of the clot).
Results
A total of 34 patients were included (15 with COVID-19 and 19 controls without COVID-19). Most of the patients were Hispanic (n=32) and delivered vaginally (85%). Of the included patients, 70% had a body mass index of >30 kg/m2. We found no statistically significant difference between the 2 groups in any of the viscoelastic measurements of hemostasis that were studied (Table ). Although the results for mean clotting time in both groups were well within the previously described normal limits for nonpregnant individuals, clot stiffness, fibrinogen contribution to clot stiffness, and platelet contribution to clot stiffness were all at the upper limit of the previously described accepted normal limits for nonpregnant individuals.
Table.
Viscoelastic measurements of hemostasis in postpartum women
| Clotting parameter | No infection (n=19) | SARS-CoV-2 infection (n=15) | P valuea |
|---|---|---|---|
| Clot time (s) | 121.5 (109–135) | 126 (94–151) | .26 |
| Clot stiffness (hectopascals) | 33.9 (14.8–44.3) | 34.8 (19–46) | .85 |
| Platelet contribution to clot stiffness (hectopascals) | 29.2 (13.2–38.2) | 29.7 (16.5–39.7) | .91 |
| Fibrinogen contribution to clot stiffness (hectopascals) | 4.4 (1.6–6.8) | 4.8 (2.5–6.3) | .96 |
Data are presented as median (range).
Pacheco. Viscoelastic testing in postpartum SARS-CoV-2 infection. Am J Obstet Gynecol 2021.
Mann-Whitney U test was used to determine significance.
Conclusion
By using viscoelastic testing, we found no evidence that asymptomatic postpartum patients infected with SARS-CoV-2 have an elevated hypercoagulable state compared with noninfected individuals. The risk for and severity of COVID-19–associated coagulopathy correlate with the severity of the disease, because the degree of inflammation and cytokine production is likely the main cause of the clotting anomalies.4 Because most pregnant women will be asymptomatic or only have a mild disease severity, the added risk for inflammation-induced clotting anomalies is likely very low. The main limitation of our study is the small sample size. The latter was mainly secondary to the difficulty of recruiting research patients during the current pandemic and the cost of viscoelastic testing. Although we cannot rule out that a small difference in coagulation parameters exist between the groups, this is likely of minimal clinical significance. Based on our findings, postpartum thromboembolism prophylaxis in this cohort should follow the current guidelines, namely early mobilization following uncomplicated vaginal delivery and sequential use of compression devices until ambulatory, following a cesarean delivery.5
Acknowledgments
Editing services were provided by LeAnne Garcia in the Publication, Grant, and Media Support Office of the Department of Obstetrics and Gynecology, The University of Texas Medical Branch at Galveston, Galveston, Texas. These services were provided to the authors at no cost as part of their affiliation with the department.
Footnotes
The authors report no conflict of interest.
This pilot study did not receive any financial support.
References
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