In agreement with studies, the following laboratory alterations were observed as a risk factors for oxygen use: decreased hemoglobin rate, lymphopenia, increased neutrophil/lymphocyte ratio, and higher levels of C-reactive protein.20, 21, 22, 23 Other predictors of clinical worsening in patients with COVID-19 in non-pregnant population cohorts, such as increased DHL, increased D-dimer, and increased creatinine, were not observed in the present study.20, 21, 22, 23, 24, 25. Here, CRP is linked to lymphopenia.