 This study investigated the levels of purine metabolites in the plasma and red blood cells of pregnant women with chronic hypertension and superimposed preeclampsia. The results indicated that these women had higher levels of purines than those found in healthy pregnant women or those with chronic hypertension alone. Additionally, the presence of elevated levels of purines was associated with increased proteinuria and thromocytopenia, suggesting that this could be an additional diagnostic criterion for preeclampsia in conjunction with proteinuria and thromocytopenia. This article was authored by Dinara Omurtaeva, Olga Panamaryova, Janna Amarbikova, and others.