No sustained effects of an intervention to prevent excessive GWG on offspring fat and lean mass at 54 weeks: Yet a greater head circumference persists

Why do preconception and pregnancy lifestyle interventions demonstrate limited success in preventing overweight and obesity in children? A scoping review investigating intervention complexity, process evaluation components, and author interpretations

Preventing childhood obesity from early life is considered essential. However, evidence from recent systematic reviews has highlighted inconsistent results and limited effectiveness of preconception and pregnancy lifestyle interventions regarding offspring weight outcomes and adiposity. Therefore, to improve our understanding regarding the mixed success of these early life interventions, we conducted a scoping review examining intervention complexity, process evaluation components, and authors' statements. Eligible articles (preconception or pregnancy lifestyle trials with offspring data beyond 1 month of age) were identified by searching databases (PubMed, Embase, and CENTRAL), previous reviews, and performing CLUSTER searches. The Intervention Complexity Assessment Tool for Systematic Reviews (iCAT_SR) was used to evaluate intervention complexity. A thematic analysis provided insight into process evaluation components and authors' interpretations. Finally, an expert consultation on the results was conducted. We identified 40 eligible publications corresponding to 27 trials. Only two trials started before conception. Potential reasons for interventions' limited success included the late intervention initiation, short intervention duration, and insufficient sample size. Few studies reported process evaluations and included stakeholder involvement, which are essential according to the expert group. We discuss current limitations and outline suggestions for future interventions in this field of research.

Body composition from birth to 2 years

Providing all infants with the best start to life is a universal but challenging goal for the global community. Historically, the size and shape of infants, quantified by anthropometry and commencing with birthweight, has been the common yardstick for physical growth and development. Anthropometry has long been considered a proxy for nutritional status during infancy when, under ideal circumstances, changes in size and shape are most rapid. Developed from data collected in the Multicentre Growth Reference Study (MGRS), WHO Child Growth Standards for healthy infants and children have been widely accepted and progressively adopted. In contrast, and somewhat surprisingly, much less is understood about the 'quality' of growth as reflected by body composition during infancy. Recent advances in body composition assessment, including the more widespread use of air displacement plethysmography (ADP) across the first months of life, have contributed to a progressive increase in our knowledge and understanding of growth and development. Along with stable isotope approaches, most commonly the deuterium dilution (DD) technique, the criterion measure of total body water (TBW), our ability to quantify lean and fat tissue using a two-compartment model, has been greatly enhanced. However, until now, global reference charts for the body composition of healthy infants have been lacking. This paper details some of the historical challenges associated with the assessment of body composition across the first two years of life, and references the logical next steps in growth assessments, including reference charts.

Prenatal interventions and the development of childhood obesity

BACKGROUND

Excess maternal adiposity during pregnancy has lasting effects on child outcomes including increased risk of overweight/obesity, which drives disease development. Prenatal interventions are a potential avenue to curb childhood obesity rates, but little is known on their long-term influence on offspring adiposity.

OBJECTIVE

Review the evidence for lasting effects of prenatal interventions on child adiposity.

METHODS

Three databases were searched for follow-up studies of completed prenatal RCTs that involved a diet, exercise, or combined (diet and exercise) intervention, and assessed offspring adiposity-related outcomes beyond birth.

RESULTS

A total of 18 follow-up studies describing 4277 offspring were included. Anthropometrics were collected in all studies while body composition was measured in 15 of the studies. Diet or exercise interventions did not have a consistent significant effect on child adiposity. Three combined interventions resulted in lower levels of child adiposity at 3, 6, and 12 months.

CONCLUSIONS

No strong association was found between prenatal diet, exercise, or combined interventions and child adiposity. Data are limited due to 63.6% overall retention rate for the follow-up studies and heterogeneity of intervention approach and child adiposity measures. Findings suggest combined interventions initiated early in pregnancy may decrease offspring adiposity in the first year of life.

Associations of maternal dietary patterns during pregnancy and fetal intrauterine development

Dietary pattern is excellent in reflecting an individual's eating conditions. Longitudinal data on fetal growth can reflect the process of intrauterine growth. We aimed to evaluate the associations between maternal dietary patterns and intrauterine parameters in middle and late pregnancy. The present study was conducted within Jiangsu Birth Cohort (JBC) study. Dietary information was assessed with a food frequency questionnaire (FFQ) in the second and third trimester of gestation. B-ultrasound scans were performed to obtain fetal intrauterine parameters, including head circumference (HC), femur length (FL), abdominal circumference (AC), and estimated fetal weight (EFW). Exploratory factor analysis was used to extract dietary patterns. Multiple linear regression and linear mixed-effects model (LMM) were used to investigate the association between maternal dietary patterns and fetal growth. A total of 1,936 pregnant women were eligible for the study. We observed inverse associations of maternal "Vegetables and fish" and "Snack and less eggs" patterns during mid-pregnancy with fetal HC Z-score, respectively ("Vegetables and fish": β = -0.09, 95% CI -0.12, -0.06; "Snack and less eggs": β = -0.05, 95% CI -0.08, -0.02). On the contrary, "Animal internal organs, thallophyte and shellfish" pattern in the second trimester was associated with increased HC Z-scores (β = 0.04, 95% CI 0.02, 0.06). Consistently, score increase in "Vegetables and fish" pattern in the third trimester was inversely associated with the Z-scores of HC (β = -0.05, 95% CI -0.09, -0.02), while "Meat and less nuts" pattern was positively correlated with the Z-scores of HC (β = 0.04, 95% CI 0.02, 0.07). As compared to the fetus whose mothers at the lowest tertile of "Snack and less eggs" pattern in both trimesters, those whose mothers at the highest tertile demonstrated 1.08 fold (RR = 2.10, 95% CI 1.34-3.28) increased risk of small HC for gestational age (GA). No correlation was observed between maternal dietary patterns and other intrauterine parameters. Our results suggested the effects of maternal dietary patterns on fetal growth, particularly HC. These findings highlighted the adverse impact of unhealthy dietary pattern on fetal growth, might provide evidence for strategies to prevent intrauterine dysplasia and dietary guidelines during pregnancy.

The effects of a lifestyle intervention (the HealthyMoms app) during pregnancy on infant body composition: Secondary outcome analysis from a randomized controlled trial

BACKGROUND

Pregnancy has been identified as a window for childhood obesity prevention. Although lifestyle interventions in pregnancy can prevent excessive gestational weight gain (GWG), little is known whether such interventions also affect infant growth and body composition.

OBJECTIVES

To investigate (i) the effects of a 6-month lifestyle intervention (the HealthyMoms app) on infant body composition 1-2 weeks postpartum, and (ii) whether a potential intervention effect on infant body composition is mediated through maternal GWG.

METHODS

This is a secondary outcome analysis of the HealthyMoms randomized controlled trial. Air-displacement plethysmography was used to measure body composition in 305 healthy full-term infants.

RESULTS

We observed no statistically significant effect on infant weight (β = -0.004, p = 0.94), length (β = -0.19, p = 0.46), body fat percentage (β = 0.17, p = 0.72), or any of the other body composition variables in the multiple regression models (all p ≥ 0.27). Moreover, we observed no mediation effect through GWG on infant body composition.

CONCLUSIONS

Our findings support that HealthyMoms may be implemented in healthcare to promote a healthy lifestyle in pregnant women without compromising offspring growth. Further research is required to elucidate whether lifestyle interventions in pregnancy also may result in beneficial effects on infant body composition and impact future obesity risk.

Anthropometric models to estimate fat mass at 3 days, 15 and 54 weeks

BACKGROUND

Currently available infant body composition measurement methods are impractical for routine clinical use. The study developed anthropometric equations (AEs) to estimate fat mass (FM, kg) during the first year using air displacement plethysmography (PEA POD® Infant Body Composition System) and Infant quantitative magnetic resonance (Infant-QMR) as criterion methods.

METHODS

Multi-ethnic full-term infants (n = 191) were measured at 3 days, 15 and 54 weeks. Sex, race/ethnicity, gestational age, age (days), weight-kg (W), length-cm (L), head circumferences-cm (HC), skinfold thicknesses mm [triceps (TRI), thigh (THI), subscapular (SCP), and iliac (IL)], and FM by PEA POD® and Infant-QMR were collected. Stepwise linear regression determined the model that best predicted FM.

RESULTS

Weight, length, head circumference, and skinfolds of triceps, thigh, and subscapular, but not iliac, significantly predicted FM throughout infancy in both the Infant-QMR and PEA POD models. Sex had an interaction effect at 3 days and 15 weeks for both the models. The coefficient of determination [R2 ] and root mean square error were 0.87 (66 g) at 3 days, 0.92 (153 g) at 15 weeks, and 0.82 (278 g) at 54 weeks for the Infant-QMR models; 0.77 (80 g) at 3 days and 0.82 (195 g) at 15 weeks for the PEA POD models respectively.

CONCLUSIONS

Both PEA POD and Infant-QMR derived models predict FM using skinfolds, weight, head circumference, and length with acceptable R2 and residual patterns.