Role of Lactate Dehydrogenase and Lymphocyte Count as Predictors of Poor Perinatal Outcomes in COVID-19-Infected Pregnancies Requiring Hospitalization and Delivery: A Retrospective Cohort Study

Introduction: Physiological, hormonal, or biochemical changes may be related to the increased morbidity of COVID-19 during pregnancy. Our knowledge remains limited about which pregnant women will worsen and develop complications. The aim was to evaluate the maternal, fetal, and neonatal outcomes in hospitalized pregnant women who delivered while infected with acute COVID-19 and to investigate the possible predictors of poor prognosis in a tertiary pandemic center.

Methods: A retrospective cohort study was conducted on pregnant women who required termination or delivery during a COVID-19 infection in a tertiary hospital. Serum markers were analyzed to determine any possible association and the predictive value of these markers to show poor maternal, fetal, and/or neonatal outcomes.

Results: Out of 45 patients, 12 had maternal complications (Group 1) and 33 had no maternal complications (Group 2). The mean lymphocyte at hospital admission was measured as 1,175.83 ± 362.0 and 1,735.30 ± 746.1 in Groups 1 and 2, respectively (p=0.02). The lymphocyte count measured at hospital admission showed significance in predicting poor maternal outcome, with an area under the curve (AUC) of 0.737 (95% CI:0.578 to 0.897) and a cut-off value of 1,110 mcL with 82% sensitivity and 67% specificity. Nineteen of the 45 women had fetal complications. Receiver operating characteristic analysis showed maternal lactate dehydrogenase as a significant predictor for poor fetal outcome with a cut-off value of 213 U/L (AUC:0.719; 95% CI:0.566 to 0.872) with 85% sensitivity and 60% specificity.

Conclusion: The lymphocyte count can be used as a predictor of poor maternal outcome and lactate dehydrogenase demonstrates poor fetal outcome during hospitalization.