Background. Preeclampsia in pregnant women is a threatening condition that causes significant water imbalance, particularly hyperhydration of the extracellular fluid compartment. The condition is the result of the main pathogenetic processes — endothelial dysfunction and the subsequent development of hypoproteinemia. The changes can be detected by measuring body water compartments. Objective: to investigate the effect of a standard intensive care on the body water compartment indicators in women with moderate to severe preeclampsia. Materials and methods. Ninety patients divided into three groups were examined: non-pregnant healthy women, pregnant women with healthy pregnancy, and women whose pregnancy was complicated by moderate to severe preeclampsia. Body water compartments were measured by non-invasive bioelectrical impedance analysis. Results. Pregnancy complicated by preeclampsia is accompanied by an increase in total fluid volume at 34–40 weeks due to an increase in both the extracellular and intracellular water compartments, but with a predominance of the extracellular compartment. By the 7th day of the postpartum period, there is a tendency to decrease the total fluid volume, however, interstitial and intracellular edema can be still observed. Conclusions. The results of the bioelectrical impe-dance analysis of the body water compartments show that additional methods of treatment are needed to correct the body water compartments in women with preeclampsia.