Purpose: The aim of this study was to evaluate the potential relationship between the left ventricle (LV) function in overweight and obese pregnant women and parameters of blood flow in uterine arteries.Methods: We conducted a prospective cohort study, which included consecutive 83 women with singleton pregnancy. They were divided into 3 groups (gr): gr. 1 - 32 (BMI ≤ 24.9 kg/m2), gr. 2 - 28 (BMI 25.0-29.9 kg/m2) and gr. 3 - 23 (BMI ≥ 30 kg/m2). During pregnancy blood pressure, echocardiography and the assessment of blood flow in uterine arteries - pulsatility index (PI) and resistance index (RI) were assessed at two visits (V): V1 between 10 and 15 weeks and V2 between 25 and 30 weeks of gestation.Results: In gr. 3 in comparison to group 1 and 2, higher systolic, diastolic, and mean arterial pressure, as well as systemic vascular resistance (SVR) were observed during V2. Traditional parameters of LV systolic function like ejection fraction and fractional shortening were slightly decreased in obese women. Although cardiac output (CO) was similar in all groups during both visits, cardiac index (CI) was significantly lower during V1 and V2 in gr.3. What is more, a negative correlation between RI measured at V2 and CI at V1 (r=-0.345, p=0.004) was found.Conclusions: Subclinical left ventricle dysfunction in obese and overweight women may contribute to placental hypoperfusion and higher resistance in uterine arteries. This may lead in some women to preeclampsia.