Objective: To evaluate the association between stunting in children and maternal short stature, controlling for potential environmental confounders. Design: 1988 Mexico National Nutrition Survey. Setting: Mexico Subjects: The ®nal sample size was 4663 pairs of children (`5 y) and their mothers (12 ± 49 y) from a total of 13 236 surveyed houses. Main outcome measures: Stunting (height-for-age Z-scores`7 2). Results: The prevalence of stunting in children was 19%, and 10% of the mothers exhibited short stature (`145 cm). In the crude analysis, mothers with short stature were signi®cantly more likely to have stunted children (odds ratio (OR) 4.0; 95% con®dence interval (CI) 3.2 ± 4.8; P-value`0.001). In a multiple logistic regression model the OR for child stunting was reduced, but remained signi®cant OR 2.0; 95% CI 1.6 ± 2.6; P-value`0.001) after adjustment for region, urbanarural residence, socio-economic status, household size, child age and presence of infection in the past 14 d, and maternal age, body mass index (BMI), and educational level. Adjusted ORs varied between regions (Mexico City, OR 3.9; North Mexico, OR 3.1; Central Mexico, OR 2.0; South Mexico, OR 1.6. Comparison of crude vs adjusted estimates pointed to regional differences in the proportion of association between maternal and child short statures explained by environmental determinants. Conclusions: Maternal stature, re¯ecting her potential height and early environment, appeared to contribute to child height independently of the shared risk factors that could affect stature. Nonetheless, we could explain much of the association between stunting in children and maternal short stature by environmental factors, and part of the residual variability may be due to unmeasured determinants. Regional differences pointed to a predominance of environmental factors in explaining child stunting in poorer regions.

Summary Objective This study aimed to examine the association of birth order and number and sex of siblings with overweight or obesity among 4- to 8-year-olds. Methods This is a cross-sectional study involving 273 low-income mother–child dyads. Questionnaires and anthropometry were completed. Multiple logistic regression was used to examine the association of birth order, having younger siblings, having older siblings, having at least one brother and having at least one sister with odds of overweight or obesity. Analyses were repeated to additionally include non-biological siblings. Models were adjusted for potential confounders and intermediate variables. Results Prevalence of child overweight or obesity was 42.5%. Adjusting for covariates, only children and youngest siblings had higher odds of overweight or obesity compared with oldest siblings (odds ratio [OR]: 4.18, 95% confidence interval [CI]: 1.67, 10.46 and OR: 3.21, 95% CI: 1.41, 7.33, respectively). Having one or more younger siblings and having at least one brother were associated with lower odds (OR: 0.38, 95% CI: 0.21, 0.69 and OR: 0.47, 95% CI: 0.28, 0.81, respectively). Including non-biological siblings did not meaningfully change the associations. Conclusion Birth order and sibship composition are associated with overweight or obesity among 4- to 8-year-olds. Future studies identifying the underlying behavioural mechanism can help inform family-based intervention programmes. Keywords: Birth order, odds of overweight or obesity, sibship composition.

Objective To examine the associations of maternal and child overweight status across multiple time‐points with liver fat content in the offspring during young adulthood. Design Cohort study. Setting ELEMENT Cohort in Mexico City. Population Pregnant women with singleton births (n = 97). Methods We quantified hepatic triglyceride content (liver fat content) by proton magnetic resonance spectroscopy (1H MRS) and conventional T2‐weighted MRIs (3T scanner) in 97 young adults from the ELEMENT birth cohort in Mexico City. Historical records of the cohort were used as a source of pregnancy, and childhood and adolescence anthropometric information, overweight and obesity (OWOB) were defined. Adjusted structural equation models were run to identify the association between OWOB in different life stages with liver fat content (log‐transformed) in young adulthood. Main outcome Maternal OWOB at the time of delivery was directly and indirectly associated with the liver fat content in the offspring at young adulthood. Results Seventeen percent of the participants were classified as having NAFLD. We found a strong association of OWOB between all periods assessed. Maternal OWOB at time of delivery (β = 1.97, 95% CI 1.28–3.05), and OWOB status in the offspring at young adulthood (β = 3.17, 95% CI 2.10–4.77) were directly associated with the liver fat content in the offspring. Also, maternal OWOB was indirectly associated with liver fat content through offspring OWOB status. Conclusion We found that maternal OWOB status is related to fatty liver content in the offspring as young adults, even after taking into account OWOB status and lifestyle factors in the offspring. Tweetable abstract There was an association between pre‐pregnancy overweight and the development of NAFLD in adult offspring.