Purpose - to analyze the maternal and perinatal outcomes of pregnancy in women with high and critical water-soluble tyrosine kinase-1/placental growth factor (sFlt-1/PlGF) ratios. Materials and methods. A prospective analysis of the course of pregnancy in 137 women with a threat of miscarriage aged 20 to 47 years was performed (the Group I - 60 patients with retrochorionic hematoma (RCH), the Group II - 77 patients with a threat of pregnancy termination without hematoma). Additionally, the level of sFlt-1/PlGF ratio was determined at gestational ages 19-23+6 weeks and 32-33+6 weeks using TRACE-technology (BRAHSMS Kryptor). Patients with a ratio value of more than 110 were included in the further study group. The antenatal risk of perinatal complications was assessed retrospectively in all patients according to the adapted Alberta perinatal health program scale. Results. The mean age of women in the Group I was 31.2±0.6 (95% CI: 30.0-32.4) years, and in the Group II - 32.2±0.6 (95% CI: 31.0-33.3) years (p=0.243 by t-test). The calculation of the risk of pre-eclampsia (PE) in women of the thematic groups using the Fetal medicine foundation (FMF) calculator «Preeclampsia risk assessment first and second trimester» revealed a high risk of its development in 28 (46.7%) women of the Group I against 23 (29.9%) women of the Group II (p=0.044 at 2). An analysis of the results of the sFlt-1/PlGF ratio at 19-23+6 weeks revealed a high or critical value in 7 (5.1%) cases. During the study of sFlt-1/PlGF at 32-33+6 weeks in both groups, cases of high or critical values of the ratio were observed in women who had no changes in the sFlt-1/PlGF ratio during the previous study at 19-23+6 weeks: in 3 cases - high value of the sFlt-1/PlGF ratio, in 1 case - critical. In all cases of high and critical levels of the ratio, the pregnancy ended prematurely due to the development of moderate or severe PE and fetal growth retardation. Conclusions. A high sFlt-1/PlGF ratio during the second half of pregnancy is associated with placental dysfunction (PD) and has a high predictive value. An important role is played by the gestational age at which these changes were first detected, as well as by a burdened medical history. The occurrence of RCH in early placentation increases the risk of developing PD and the obstetric complications associated with it. The research was carried out in accordance with the principles of the Helsinki Declaration. The study protocol was approved by the Local Ethics Committee of the participating institution. The informed consent of the patient was obtained for conducting the studies. No conflict of interests was declared by the authors.