Ganho de peso gestacional: uma análise comparativa entre as recomendações do Institute of Medicine (IOM) e as novas curvas Brasileiras

Pregnancy is a complex phenomenon that involves multiple factors, with emphasis on gestational weight gain (GWG). Adequate GWG is essential to ensure maternal and child health; however, both excessive and insufficient GWG can lead to unfavorable health outcomes for both. In view of changes in GWG, the Brazilian Ministry of Health recommends monitoring weight and assessing nutritional status during prenatal care in order to prevent possible complications. Thus, the tools used to monitor GWG are based on the Institute of Medicine (IOM) 2009. Although this is a guideline adopted worldwide, it was created for North American pregnant women and may not be suitable for the Brazilian population. Given the epidemiological situation of female obesity in Brazil, Brazilian researchers from the Nutritional Epidemiology Observatory of the Federal University of Rio de Janeiro (UFRJ) developed, in 2021 and 2022, New Curves and GWG recommendations for the Brazilian population, which were then adopted by the Ministry of Health at the end of 2022. Thus, the objective of this study was to compare the GWG percentage between the IOM GWG recommendations and the New Brazilian Curves, and also to verify whether food consumption was compatible with the GWG. This is a retrospective cross-sectional study, including 58 women aged 18 to 43 years, between the end of the 3rd gestational trimester and 5 days postpartum. Data on pre-gestational weight and height were collected to calculate pre-gestational BMI, classified as: underweight, eutrophy, overweight and obesity. Socioeconomic, health, and food consumption data of pregnant women were also collected, as well as the birth weight of their babies. According to the IOM recommendations, 12 women (20.68%) had insufficient GWG, 23 (39.66%) adequate, and 23 (39.66%) excessive. With the New Curves, 8 (13.79%) had insufficient GWG, 10 (17.24%) adequate, and 40 (68.97%) excessive. It is possible to verify that excess weight is more frequent in the New Curves recommendations, which means that it detects more excess weight than the IOM. Regarding the recommended caloric intake based on the Estimated Energy Requirements (EER) 2023 and Recommended Dietary Allowance (RDA) 1989, it is clear that the energy recommendation of the RDA 1989 is more compatible with the amount of energy that the pregnant woman reported consuming. Obese women consume less natural foods and more ultra-processed foods. In addition, pregnant women who gained more weight during pregnancy had a higher frequency of births of larger babies. However, only 1 child was born large for gestational age. Conclusion: This study suggests that the New GWG Curves identify a higher percentage of pregnant women with excessive GWG than the IOM classification. Pregnant women with excessive GWG, classified by both the IOM and the New Curves, had larger babies at birth without adverse outcomes. The New Curves represent an important step towards a more accurate assessment of GWG in Brazilian pregnant women, with the potential to contribute to the reduction of GWG and weight retention after delivery