# Adequacy of gestational weight gain according to the brazilian charts: a comparison with the Institute of Medicine recommendations

## TL;DR

This study compares gestational weight gain patterns in Brazilian women using national charts versus U.S. guidelines, finding higher rates of excessive weight gain with the Brazilian method.

## Contribution

The study provides a novel comparison of gestational weight gain classifications using Brazilian charts versus IOM standards in a mixed-risk pregnancy population.

## Key findings

- Brazilian charts showed higher prevalence of excessive GWG (53.1%) compared to IOM standards.
- Pregestational BMI and nutritionist consultations were significant modifiable factors influencing GWG.
- Brazilian charts had better sensitivity and specificity for detecting excessive GWG than insufficient GWG.

## Abstract

To analyze the adequacy of gestational weight gain (GWG) and associated factors, according to the Brazilian GWG charts, and compare with the Institute of Medicine (IOM) recommendations.

This was a cross-sectional study. Sociodemographic, clinical, and obstetric data were collected from interviews and medical records. The sample was divided into three groups according to the Brazilian charts: insufficient GWG, adequate GWG, and excessive GWG. The chi-square and Kruskal-Wallis tests were used to compare frequencies and medians, respectively, and Dunn's test was used to verify differences between groups, assuming statistical significance of p<0.05.

Seven hundred and twenty-five women with low-and high-risk pregnancies were evaluated. Using the Brazilian charts, the prevalence of insufficient, adequate, and excessive GWG was 25.8%, 21.1%, and 53.1%, respectively. Compared with the classifications given using the IOM method, there was a lower prevalence of insufficient and adequate GWG and a higher prevalence of excessive GWG. The sensitivity and specificity of the Brazilian charts versus the IOM recommendations were 100% and 76.6%, respectively, for excessive GWG and 72.3% and 20%, respectively, for insufficient GWG. The modifiable factors related to GWG were pregestational BMI (p=0.001) and number of consultations with a nutritionist (p=0.008).

Studies evaluating the Brazilian GWG charts are scarce. The Brazilian charts indicated a higher prevalence of excessive GWG than the IOM recommendations. The sensitivity and specificity of the Brazilian charts were better for excessive GWG than for insufficient GWG, using the IOM recommendations as the standard.