Introduction. Adverse pregnancy outcomes are less common among physically active women, and children born to such mothers are less likely to be at risk for macrosomia, obesity and metabolic diseases in the future. Objectives. The aims of the study were to establish physical activity (PA) patterns among pregnant women in the third trimester, and to determine the attitudes of prenatal care providers to maternal PA during pregnancy. Materials and method. The study was conducted in 2017 using surveys from the Polish Pregnancy-related Assessment Monitoring System program (Pol-PrAMS). The study included 3,451 postpartum women. The Pregnancy Physical Activity Questionnaire was used to investigate their PA. This part of Pol-PrAMS study was completed by 2,744 postpartum women who were subjected to statistical analysis. Results. Sedentary or light physical activity comprised 75% of the overall PA in the third trimester of pregnancy (mean values of energy expenditure: 67 and 93.3 MET-h/week, respectively). Household or caregiving activities accounted for almost 50% of all activities and were the most common PA types (mean energy expenditure: 105 MET-h/week). Restriction of PA in pregnancy was reported by over 60% of the women, most often due to concerns over proper foetal development. Over 85% of prenatal care providers either did not address the issue of PA with the future mothers at all, or recommended PA restriction. Conclusions. Sedentary and light-intensity PA are the two predominant types of physical activity in the third trimester. The most energy-consuming tasks involve household and caregiving activities. Restriction of activity was reported by the majority of the respondents. Prenatal care providers either did not address the matter of PA in pregnancy or recommended PA restriction.