Variations in estimates of underweight, overweight, and obesity in pregnant women from Argentina comparing two reference charts

Objectives The prevalence of low weight, normal weight, overweight, and obesity in a sample of Argentinian pregnant women using two reference charts, the Rosso and Mardones (RM) and the Calvo Chart were compared. Methods A descriptive, cross‐sectional, comparative study of data from pregnant women beneficiaries of food aid programs collected in the period 2003–2010 in the province of Buenos Aires, Argentina was performed. Results Evaluations with the Calvo and RM charts showed statistically significant differences in the prevalence of all nutritional conditions (low weight, 22% vs. 28%; normal weight, 45% vs. 28%; overweight, 21% vs. 15%; obesity, 11% vs. 29%, respectively). Such differences were more marked in normal weight and obese pregnant women. Conclusions Changes in prevalences as a result of replacing the RM with the Calvo Chart should be borne in mind to avoid misinterpretations about changes in the nutritional condition of pregnant women.