Objective To synthesise evidence from contemporary populations (2009-24) across diverse world regions and income settings on associations between gestational weight gain (GWG) and broad clinical outcomes, to inform updated, globally relevant GWG standards. Design Systematic review and meta-analysis. Setting Observational studies in all languages, with >300 participants, reporting pregnancy outcomes stratified by body mass index (BMI) and GWG. Participants Women aged >18 years with singleton pregnancies. Main outcome measures Birth weight and rates of caesarean delivery, hypertensive disorders of pregnancy, preterm birth, small/large for gestational age infant, low birth weight, macrosomia, neonatal intensive care unit (NICU) admission, respiratory distress, hyperbilirubinaemia, and gestational diabetes. Results Of 16 030 studies, 40 met inclusion criteria (n=1 608 711); 6% (n=65 114) of women had underweight, 53% (n=607 258) had normal weight, 19% (n=215 183) had overweight, and 22% (n=252 970) had obesity. GWG was below or above Institute of Medicine (IOM) or study specific recommendations in 23% and 45%, respectively. Using World Health Organization BMI criteria, GWG below IOM recommendations was associated with lower birth weight (mean difference −184.54, 95% confidence interval −278.03 to −91.06); lower risk of caesarean delivery (odds ratio 0.90, 0.84 to 0.97), large for gestational age infant (0.67, 0.61 to 0.74), and macrosomia (0.68, 0.58 to 0.80); and higher risk of preterm birth (1.63, 1.33 to 1.90), small for gestational age infant (1.49, 1.37 to 1.61), low birth weight (1.78, 1.48 to 2.13), and respiratory distress (1.29, 1.01 to 1.63). GWG above IOM recommendations was associated with higher birth weight (mean difference 118.33, 53.80 to 182.85); higher risk of caesarean delivery (odds ratio 1.37, 1.30 to 1.44), hypertensive disorders of pregnancy (1.37, 1.28 to 1.48), large for gestational age infant (1.77, 1.62 to 1.94), macrosomia (1.78, 1.60 to 1.99), and NICU admission (1.26, 1.09 to 1.45); and lower risk of preterm birth (0.71, 0.64 to 0.79) and small for gestational age infant (0.69, 0.64 to 0.75). For Asian BMI criteria, GWG below recommendations was associated with higher risk of hypertensive disorders of pregnancy (3.58, 1.37 to 9.39) and preterm birth (1.69, 1.25 to 2.30) and lower risk of large for gestational age infant (0.80, 0.72 to 0.89). GWG above recommendations was associated with higher risk of caesarean delivery (1.37, 1.29 to 1.46) and large for gestational age infant (1.76, 1.42 to 2.18) and lower risk of small for gestational age infant (0.62, 0.53 to 0.74) and low birth weight (0.44, 0.31 to 0.6). Conclusions This systematic review captured trends of rising maternal age and BMI from diverse world regions and income settings, with broad outcomes across all BMI groups. GWG outside IOM recommendations was associated with increased risk of adverse outcomes. These findings will help to inform the process of the WHO initiative to optimise globally relevant GWG standards for improved perinatal outcomes across world regions. Study registration PROSPERO CRD42023483168.

A high-quality diet during pregnancy may have positive effects on fetal growth and nutritional status at birth, and it may modify the risk of developing chronic diseases later in life. The aim of this study was to evaluate the association between diet quality and newborn nutritional status in a group of pregnant Mexican women. As part of the ongoing Mexican prospective cohort study, OBESO, we studied 226 healthy pregnant women. We adapted the Alternated Healthy Eating Index-2010 for pregnancy (AHEI-10P). The association between maternal diet and newborn nutritional status was investigated by multiple linear regression and logistic regression models. We applied three 24-h recalls during the second half of gestation. As the AHEI-10P score improved by 5 units, the birth weight and length increased (β = 74.8 ± 35.0 g and β = 0.3 ± 0.4 cm, respectively, p < 0.05). Similarly, the risk of low birth weight (LBW) and small for gestational age (SGA) decreased (OR: 0.47, 95%CI: 0.27–0.82 and OR: 0.55, 95%CI: 0.36–0.85, respectively). In women without preeclampsia and/or GDM, the risk of stunting decreased as the diet quality score increased (+5 units) (OR: 0.62, 95%IC: 0.40–0.96). A high-quality diet during pregnancy was associated with a higher newborn size and a reduced risk of LBW and SGA in this group of pregnant Mexican women.

This study aims to compare the effects of a lifestyle intervention using a behavioral therapy (BT) approach with the effects of a cardioprotective structured hypocaloric diet on metabolic syndrome in Mexican postmenopausal women. This study is a randomized clinical trial (2006-2009) of Mexican postmenopausal women with metabolic syndrome (Adult Treatment Panel III criteria) who were recruited from the Postmenopause Clinic of the National Institute of Perinatology in Mexico City. Women were assigned to one of two groups--group 1 (structured hypocaloric diet; n = 63): energy restriction (-300 to -500 kcal/d) emphasizing cardioprotective dietary changes; and group 2 (BT; n = 55): goal setting, problem-solving, and stimulus control to achieve cardioprotective dietary and lifestyle recommendations. Metabolic syndrome prevalence, as well as weight, waist circumference, fat mass, and fasting biochemical markers (glucose and lipid profile), were measured at baseline and at 2, 4, and 6 months after the intervention. Metabolic syndrome risk (relative risk and absolute risk reduction), mean differences between groups, and logistic regression were evaluated using Statistical Package for the Social Sciences software, version 17.0. A total of 118 women were studied (mean [SD] age, 53.81 [6.43] y). No baseline differences were observed between groups. At the end of the study, a higher reduction in metabolic syndrome prevalence was observed in group 1 (-38.1%) compared with group 2 (-12.7%; relative risk, 0.237; 95% CI, 0.092-0.608; P = 0.003). The effect was maintained even when adjusted by age, hormone therapy and antihypertensive drug use. A cardioprotective structured hypocaloric diet is more effective than the BT approach in reducing metabolic syndrome after 6 months of intervention. Both strategies have positive effects on different individual cardiovascular risk factors.

Body composition in infancy plays a central role in the programming of metabolic diseases. Fat mass (FM) is determined by personal and environmental factors. Anthropometric measurements allow for estimations of FM in many age groups; however, correlations of these measurements with FM in early stages of life are scarcely reported. The aim of this study was to evaluate anthropometric and clinical correlates of FM in healthy term infants at 6 months of age. Healthy term newborns (n = 102) from a prospective cohort. Weight, length, skinfolds (biceps, triceps, subscapular and the sum -SFS-) and waist circumference (WC) were measured at 6 months. Body mass index (BMI) and WC/length ratio were computed. Type of feeding during the first 6 months of age was recorded. Air displacement plethysmography was used to asses FM (percentage -%-) and FM index (FMI) was calculated. Correlations and general linear models were performed to evaluate associations. Significant correlations were observed between all anthropometric measurements and FM (% and index)(p < 0.001). Exclusive/predominant breastfed infants had higher FM and anthropometric measurements at 6 months. Models that showed the strongest associations with FM (% and index) were SFS + WC + sex + type of feeding. Anthropometry showed good correlations with FM at 6 months of age. Skinfolds sum and waist circumference were the strongest anthropometric variables associated to FM. Exclusive/predominant breastfeeding was strongly associated with FM.

This work aimed to identify clinical practice guidelines (CPGs) that include recommendations for the prevention, diagnosis, and treatment of women’s malnutrition during pregnancy and to evaluate the quality of these guidelines using the Appraisal of Guidelines for Research and Evaluation (AGREE II) instrument. We conducted a literature review using PubMed and different websites from January 2009 to February 2021. The quality of the CPGs was independently assessed by reviewers using the AGREE II instrument, which defines guidelines scoring >70% in the overall assessment as “high quality”. The analysis included 43 guidelines. Among the main findings, we identified that only half of the CPGs (51.1%) obtained a final “high quality” evaluation. AGREE II results varied widely across domains and categories. The two domains that obtained the highest scores were scope and purpose with 88.3% (range 39 to 100%) and clarity of presentation with 87.2% (range 25 to 100%). Among the “high quality” CPGs, the best scores were achieved by the three guidelines published by the National Institute of Health and Care Excellence (NICE) and the World Health Organization (WHO). Due to the importance of maternal nutrition in pregnancy, it is essential to join forces to improve the quality of the guidelines, especially in CPGs that do not meet the reference standards for quality.