Epidemiology of obesity in pregnancy in the Czech Republic – demographic context and clinical implications

Abstract

Objective: To describe the current epidemiology of overweight and obesity among pregnant women in Czechia in the context of demographic trends and basic perinatal outcomes. Materials and methodology: The analysis was based on data from the National Reproductive Health Registry (NRRZ) from April 1 to September 30, 2025, focusing on 1^st trimester BMI. Since April 1, 2025, the new Registry Report systematically records women’s height and weight at the beginning and the end of pregnancy. First-trimester BMI and its associations with selected demographic characteristics (particularly age, education, and parity) and selected clinical indicators of pregnancy and delivery outcomes were evaluated. For comparison, data from the European Union Statistics on Income and Living Conditions (EU-SILC) and European Health Interview Survey (EHIS) were also used. A total of 23,573 women with complete 1^st trimester BMI data were included in the analysis. Results and conclusion: Among the 23,573 pregnant women with available BMI data, 53.4% were normal weight, 24.3% were overweight, and 17.7% were obese. Overweight and obesity were more frequent among older women, had lower educational attainment, and higher parity. Higher BMI was associated with an increased risk of preterm birth, foetal macrosomia, caesarean section, gestational hypertension, preeclampsia, and gestational diabetes. Overweight and obesity affect more than 40% of pregnant women in Czechia representing a significant risk factor for adverse perinatal outcomes. Systematic data collection allows, for the first time, a detailed national analysis and provides a basis for preventive interventions.