The best cut-off value of sFlt-1/PlGF ratio for severe COVID-19 prediction was 46.3, with a sensitivity of 0.54 (95% CI 0.4–0.8), specificity of 0.85 (95% CI 0.8–0.9), positive likelihood ratio of 3.67 (95% CI 2.1–6.5) and negative likelihood ratio of 0.54 (0.4–0.7). Here, PGF is linked to COVID-19.