Predictors of inadequate gestational weight gain according to iom recommendations and intergrowth-21st standards: the araraquara cohort study.

BACKGROUND: Gestational weight gain (GWG) is a critical factor for maternal and fetal health. OBJECTIVE: To identify maternal predictors of inadequate GWG according to the 2009 Institute of Medicine (IOM) recommendations and Intergrowth-21st standards. METHODS: A prospective epidemiological cohort study conducted from 2017 to 2023 in southeastern Brazil assessed 1,557 women at three different stages of pregnancy (≤ 18, 20-26, and 30-36 weeks of gestation) and at delivery. Sociodemographic, obstetric, lifestyle, nutritional, and maternal morbidity characteristics were collected, along with biochemical parameters. RESULTS: Among the participants, 38.7% had GWG above IOM recommendations, while 67.5% had GWG above the Intergrowth-21st standards. Multinomial logistic regression analysis showed that women with pre-pregnancy obesity and women with the highest body fat percentage had, respectively, a 95% (OR = 1.95; 95% CI: 1.08-3.51) and 1% (OR = 1.01; 95% CI: 1.01-1.05) higher chance of GWG above IOM recommendations. Pregnant women in the lowest tertile of height, smokers, number of previous pregnancies, and women living in crowded homes had, respectively, a 57% (OR = 0.57; 95% CI: 0.41-0.80), 36% (OR = 0.64; 95% CI: 0.37-0.86), 35% (OR = 0.65; 95% CI: 0.43-0.97), and 14% (OR = 0.86; 95% CI: 0.59-0.86) lower chance of GWG above IOM recommendations. Women with diabetes were 2.53 times more likely (OR = 2.53; 95% CI: 1.32-4.83) to have GWG below IOM recommendations. Using the Intergrowth-21st standards, women with the highest body fat percentage had a 12% (OR = 1.12; 95% CI: 1.02-1.24) higher chance of GWG above the 90th percentile. Pregnant women in the lowest tertile of height were 2.82 times more likely (OR = 2.82; 95% CI: 1.08-8.13) and women with the lowest hemoglobin concentrations had a 41% lower chance (OR = 0.59; 95% CI: 0.39-0.88) of having GWG below the 10th percentile. While both guidelines identified body fat percentage and pre-pregnancy obesity as significant predictors of excessive GWG, the Intergrowth-21st standards captured a higher percentage of women exceeding GWG limits. CONCLUSION: The findings underscore the importance of comparing two instruments for assessing the adequacy of GWG. The IOM and Intergrowth-21st standards provide complementary insights, which can help implement targeted interventions for specific groups of women based on their nutritional and socioeconomic status, lifestyle, and obstetric factors to prevent pregnancy-related complications.

The impact of gestational weight gain on fetal and neonatal outcomes: the Araraquara Cohort Study.

BACKGROUND: Gestational weight gain (GWG) is an important indicator for monitoring maternal and fetal health. OBJECTIVE: To evaluate the effect of GWG outside the recommendations of the Institute of Medicine (IOM) on fetal and neonatal outcomes. STUDY DESIGN: A prospective cohort study with 1642 pregnant women selected from 2017 to 2023, with gestational age ≤ 18 weeks and followed until delivery in the city of Araraquara, Southeast Brazil. The relationship between IOM-recommended GWG and fetal outcomes (abdominal subcutaneous tissue thickness, arm and thigh subcutaneous tissue area and intrauterine growth restriction) and neonatal outcomes (percentage of fat mass, fat-free mass, birth weight and length, ponderal index, weight adequateness for gestational age by the Intergrowth curve, prematurity, and Apgar score) were investigated. Generalized Estimating Equations were used. RESULTS: GWG below the IOM recommendations was associated with increased risks of intrauterine growth restriction (IUGR) (aOR 1.61; 95% CI: 1.14-2.27), low birth weight (aOR 2.44; 95% CI: 1.85-3.21), and prematurity (aOR 2.35; 95% CI: 1.81-3.05), and lower chance of being Large for Gestational Age (LGA) (aOR 0.38; 95% CI: 0.28-0.54), with smaller arm subcutaneous tissue area (AST) (-7.99 g; 95% CI: -8.97 to -7.02), birth length (-0.76 cm; 95% CI: -1.03 to -0.49), and neonatal fat mass percentage (-0.85%; 95% CI: -1.12 to -0.58). Conversely, exceeding GWG guidelines increased the likelihood of LGA (aOR 1.53; 95% CI: 1.20-1.96), with lower 5th-minute Apgar score (aOR 0.42; 95% CI: 0.20-0.87), and increased birth weight (90.14 g; 95% CI: 53.30 to 126.99). CONCLUSION: Adherence to GWG recommendations is crucial, with deviations negatively impacting fetal health. Effective weight control strategies are imperative.