CAT and COVID-19: On the other hand, CAT activity decreased in the COVID-19 group (p < 0.01 in placenta and p < 0.05 in serum), while an increase in 8-hydroxy-2’-deoxyguanosine (8-OHdG) (p < 0.01 for placenta and serum), hydroperoxides (p < 0.001 for placenta), 15-FT-isoprostanes (p < 0.01 for placenta and serum), and carbonyl groups (p < 0.001 for placenta and p < 0.05 for serum) were recorded in the COVID-19 group.