Greater maternal weight gain during pregnancy predicts a large but lean fetal phenotype: a prospective cohort study

Sex-dependent influence of maternal predictors on fetal anthropometry in pregnancies with gestational diabetes mellitus

Background

Third trimester fetal anthropometric parameters are known to predict neonatal complications. A better understanding of predictors of adverse fetal parameters might help to personalize the use and frequency of fetal ultrasound. The objectives of this study were:

(a) to evaluate the utility of maternal sociodemographic, anthropometric and metabolic predictors to predict 3^rd trimester fetal anthropometric parameters in women with gestational diabetes mellitus (GDM),

(b) to assess whether the impact of these maternal predictors is fetal sex-dependent, and

(c) to provide a risk stratification for markers of fetal overgrowth (fetal weight centile (FWC) and fetal abdominal circumference centile (FACC) depending on prepregnancy BMI and gestational weight gain (GWG) until the 1^st GDM visit.

Methods

This prospective study included 189 women with GDM. Maternal predictors were age, ethnicity, prepregnancy BMI, GWG and excessive weight gain until the 1^st GDM visit, fasting, 1-hour and 2-hour blood glucose oral glucose tolerance test values, HbA1c at the 1^st visit and medical treatment requirement. Fetal outcomes included FWC, FWC >90% and <10%, FACC, FACC >90% and <10%, at 29 0/7 to 35 6/7 weeks of gestational age. We performed univariate and multivariate regression analyses and probability analyses.

Results

In multivariate analyses, prepregnancy BMI was associated with FWC, FWC > 90% and FACC. GWG until the 1^st GDM visit was associated with FWC, FACC and FACC > 90% (all p ≤ 0.045). Other maternal parameters were not significantly associated with fetal anthropometry in multivariate analyses (all p ≥ 0.054). In female fetuses, only GWG was associated with FACC (p= 0.044). However, in male fetuses, prepregnancy BMI was associated with FWC, FWC > 90% and FACC and GWG with FWC in multivariate analyses (all p ≤ 0.030). In women with a prepregnancy BMI of ≥ 25 kg/m² and a GWG until the 1^st GDM visit ≥ 10.3 kg (mean GWG), the risk for FWC > 90% and FACC > 90% was 5.3 and 4 times higher than in their counterparts.

Conclusions

A personalized fetal ultrasound surveillance guided by fetal sex, prepregnancy BMI and GWG may be beneficial in reducing adverse fetal and neonatal outcomes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-022-04767-z.

Modeling the Predictive Value of Evidence-Based Referral Criteria to Support Healthy Gestational Weight Gain among an Australian Pregnancy Cohort

Globally, there has been a renewed focus on addressing gestational weight gain (GWG). In Australia, the Department of Health pregnancy care guidelines recommend women be offered routine weighing and receive brief nutritional and physical activity support during antenatal care visits. Women gaining weight outside the Institute of Medicine (IOM)'s weight gain reference values are further recommended to be referred to a dietitian. However, professional and organizational barriers, including an absence of weight gain referral pathways and limited workforce resources, exist with the translation and scaling of these recommendations into practice. This study aimed to explore patterns of GWG among a cohort of Australian pregnant women and to determine if pregnancy weight gains of above or below 2 kg or 5 kg in the second and third trimester can be used to predict total GWG outside recommendations. Sensitivity, specificity, negative, and positive likelihood ratios were calculated. The most predictive time point was 24 weeks' gestation using the minimum weight change parameter of +/-2 kg, demonstrating reasonable sensitivity (0.81, 95% CI 0.61-0.83) and specificity (0.72, 95% CI 0.61-0.83), resulting in 55% (n = 72/131) of the cohort qualifying for dietetic referral. Given the current health service constraints, a review of dietetic services within maternity care is warranted.

Macronutrient Intake in Pregnancy and Child Cognitive and Behavioural Outcomes

Prenatal nutrient exposures can impact on brain development and disease susceptibility across the lifespan. It is well established that maternal macronutrient intake during pregnancy influences foetal and infant development. Therefore, we hypothesise that macronutrient intakes during pregnancy are correlated with cognitive development during early childhood. The current study aimed to investigate the relationship between maternal macronutrient intake during pregnancy and child cognitive and behavioural outcomes at age 4 years. We analysed prospective data from a cohort of 64 Australian mother-child dyads. Maternal macronutrient intake was assessed using a validated 74-item food frequency questionnaire at 2 timepoints during pregnancy. Child cognition and behaviour were measured at age 4 years using the validated Wechsler Preschool and Primary Scale of Intelligence, 3rd version (WPPSI-III) and the Child Behaviour Checklist (CBC). Linear regression models were used to quantify statistical relationships and were adjusted for maternal age, education, pre-pregnancy BMI, breastfeeding duration and birthweight. Child Performance IQ was inversely associated with maternal starch intake (b = -11.02, p = 0.03). However, no other associations were found. Further research is needed to explore the association between different types of starch consumed during pregnancy and child cognitive development.

In overweight and obese women, fetal ultrasound biometry accurately predicts newborn measures

INTRODUCTION

The aim of this study was to evaluate the association between fetal ultrasound and newborn biometry and adiposity measures in the setting of maternal obesity.

MATERIAL AND METHODS

The study population involved 845 overweight or obese pregnant women, who participated in the Standard Care Group of the LIMIT randomised trial (ACTRN12607000161426, 9/03/2007). At 36 weeks gestation, fetal biometry, estimated fetal weight (EFW) and adiposity measures including mid-thigh fat mass (MTFM), subscapular fat mass (SSFM), and abdominal fat mass (AFM) were undertaken using ultrasound. Neonatal anthropometric measurements obtained after birth included birthweight, head circumference (HC), abdominal circumference (AC) and skinfold thickness measurements (SFTM) of the subscapular region and abdomen.

RESULTS

At 36 weeks gestation, every 1 g increase in EFW was associated with a 0.94 g increase in birthweight (95% CI 0.88-0.99; P < 0.001). For every 1 mm increase in the fetal ultrasound measure, there was a 0.69 mm increase in birth HC (95% CI 0.63-0.75, P < 0.001) and 0.69 mm increase in birth AC (95% CI 0.60-0.79, P < 0.001). Subscapular fat mass in the fetus and the newborn (0.29 mm, 95% CI 0.20-0.39, P < 0.001) were moderately associated, but AFM measurements were not (0.06 mm, -0.03 to 0.15, P = 0.203). There is no evidence that these relationships differed by maternal body mass index.

CONCLUSION

In women who are overweight or obese, fetal ultrasound accurately predicts neonatal HC and AC along with birthweight.

Measuring fetal adipose tissue using 3D water-fat magnetic resonance imaging: a feasibility study

Purpose: Analysis of fetal adipose tissue volumes may provide useful insight towards assessment of overall fetal health, especially in cases with abnormal fetal growth. Here, we assess whether fetal adipose tissue volume can be reliably measured using 3D water-fat MRI, using a quantitative assessment of the lipid content of tissues.Materials and methods: Seventeen women with singleton pregnancies underwent a fetal MRI and water-only and fat-only images were acquired (modified 2-point Dixon technique). Water and fat images were used to generate a fat signal fraction (fat/(water + fat)) from which subcutaneous adipose tissue was segmented along the fetal trunk. Inter-rater (three readers) and intrarater reliability was assessed using intraclass-correlation coefficients (ICC) for 10 image sets. Relationships between adipose tissue measurements and gestational age and estimated fetal weight percentiles were examined.Results: The ICC of the inter-rater reliability was 0.936 (p < .001), and the ICC of the intrarater reliability was 0.992 (p < .001). Strong positive correlations were found between adipose tissue measurements (lipid volume, lipid volume/total fetal volume, mean fat signal fraction) and gestational age.Conclusions: 3D water-fat MRI can reliably measure volume and quantify lipid content of fetal subcutaneous adipose tissues.

Is parity a risk factor for excessive weight gain during pregnancy and postpartum weight retention? A systematic review and meta-analysis

The aim of this study was to systematically review and meta-analyse the associations between parity, pre-pregnancy body mass index (BMI), gestational weight gain (GWG) and, when included, postpartum weight retention (PPWR). Papers reporting associations between parity and BMI and/or GWG in adult women were eligible: 2,195 papers were identified, and 41 longitudinal studies were included in the narrative synthesis; 17 studies were included in a meta-analysis. Findings indicated that parity was associated positively with pre-pregnancy BMI. In contrast, the role of parity in GWG was less clear; both positive and negative relationships were reported across studies. Parity was not associated directly with PPWR. This pattern of results was supported by our meta-analysis with the only significant association between parity and pre-pregnancy BMI. Overall, parity was associated with higher pre-pregnancy BMI; however, the role of parity in GWG and PPWR remains unclear, and it is likely that its influence is indirect and complex. Further research to better understand the contribution of parity to maternal obesity is warranted.

Lifestyle intervention to prevent obesity during pregnancy: Implications and recommendations for research and implementation

Maternal obesity and excessive gestational weight gain (GWG) are significant contributors to the global obesity epidemic. However, isolated lifestyle interventions to address this in pregnancy appear to have only modest benefit and responses can be variable. This paper aims to address the question of why the success of lifestyle interventions to prevent excessive GWG is suboptimal and variable. We suggest that there are inherent barriers to lifestyle change within pregnancy as a life stage, including the short window available for habit formation; the choice for women not to prioritise their weight; competing demands including physiological, financial, relationship, and social situations; and lack of self-efficacy among healthcare professionals on this topic. In order to address this problem, we propose that just like all successful public health approaches seeking to change behaviour, individual lifestyle interventions must be provided in the context of a supportive environment that enables, incentivises and rewards healthy changes. Future research should focus on a systems approach that integrates the needs of individuals with the context within which they exist. Borrowing from the social marketing principle of 'audience segmentation', we also need to truly understand the needs of individuals to design appropriately tailored interventions. This approach should also be applied to the preconception period for comprehensive prevention approaches. Additionally, relevant policy needs to reflect the changing evidence-based climate. Interventions in the clinical setting need to be integrally linked to multipronged obesity prevention efforts in the community, so that healthy weight goals are reinforced throughout the system.

Differences in the anthropometry of Asian children and its role in metabolic health in later life: A narrative review

BACKGROUND

The increasing incidence of childhood obesity in Asia could be a reflection of early life programming in which environmental/nutritional challenges during pregnancy and first two years of life (the so-called first 1000 days) influence later health.

OBJECTIVE OF NARRATIVE REVIEW

To assess differences/similarities of anthropometric measures in early life and their influences on metabolic health risk in later life among children in Asia.

METHODS

Literature search for publication in English using selected key words from Medline (PubMed), Scopus, Science Direct and Google Scholar published from 1994 to October 2014. Some comparisons with Caucasian setting were made when relevant.

RESULTS

From 152 publications selected for this narrative review, differences in foetal growth and birth weight were deducted between Asian and Caucasian children. Infants in India and Hong Kong had increased fat mass at birth and early infancy as compared to those from other parts of the world. Pre- and during pregnancy conditions influenced birth weight; feeding practices and gender influenced post-natal growth and body composition development. High and low birth weights followed by rapid postnatal growth were linked to increased risks of obesity, insulin resistance and high blood pressure in later life.

CONCLUSION

Foetal and postnatal growth trajectories are different between countries within and outside Asia. Extremes in birth weight followed by rapid postnatal growth were linked to increased risks of metabolic health of children in this region. As there is limited evidence in Asia, it is important to conduct thorough investigations by using longitudinal studies on early life programming.

Antenatal dietary and lifestyle advice for women who are overweight or obese and the effect on fetal growth and adiposity: the LIMIT randomised trial

OBJECTIVE

To report the influence of maternal overweight and obesity on fetal growth and adiposity and effects of an antenatal dietary and lifestyle intervention among these women on measures of fetal growth and adiposity as secondary outcomes of the LIMIT Trial.

DESIGN

Randomised controlled trial.

SETTING

Public maternity hospitals in metropolitan Adelaide, South Australia.

POPULATION

Pregnant women with a body mass index ≥ 25 kg/m(2), and singleton gestation between 10(+0) and 20(+0) weeks.

METHODS

Women were randomised to Lifestyle Advice or continued Standard Care and offered two research ultrasound scans at 28 and 36 weeks of gestation.

MAIN OUTCOME MEASURES

Ultrasound measures of fetal growth and adiposity.

RESULTS

For each fetal body composition parameter, mean Z-scores were substantially higher when compared with population standards. Fetuses of women receiving Lifestyle Advice demonstrated significantly greater mean mid-thigh fat mass, when compared with fetuses of women receiving Standard Care (adjusted difference in means 0.17; 95% CI 0.02-0.32; P = 0.0245). While subscapular fat mass increased between 28 and 36 weeks of gestation in fetuses in both treatment groups, the rate of adipose tissue deposition slowed among fetuses of women receiving Lifestyle Advice, when compared with fetuses of women receiving Standard Care (P = 0.0160). No other significant differences were observed.

CONCLUSIONS

These findings provide the first evidence of changes to fetal growth following an antenatal dietary and lifestyle intervention among women who are overweight or obese.

Early life nutrition and the opportunity to influence long-term health: an Australasian perspective

There are now significant data to support the hypothesis that early life nutrition in the fetus, infant and young child can have profound effects on long-term health. This review considers some of this evidence with specific reference to the current burden of disease in Australia and New Zealand. As the findings of further research become available, recommendations on optimizing early life nutrition should be formulated and made widely available as part of the preventative health policy agenda in both Australia and New Zealand.

Body composition during fetal development and infancy through the age of 5 years

Fetal body composition is an important determinant of body composition at birth, and it is likely to be an important determinant at later stages in life. The purpose of this work is to provide a comprehensive overview by presenting data from previously published studies that report on body composition during fetal development in newborns and the infant/child through 5 years of age. Understanding the changes in body composition that occur both in utero and during infancy and childhood, and how they may be related, may help inform evidence-based practice during pregnancy and childhood. We describe body composition measurement techniques from the in utero period to 5 years of age, and identify gaps in knowledge to direct future research efforts. Available literature on chemical and cadaver analyses of fetal studies during gestation is presented to show the timing and accretion rates of adipose and lean tissues. Quantitative and qualitative aspects of fetal lean and fat mass accretion could be especially useful in the clinical setting for diagnostic purposes. The practicality of different pediatric body composition measurement methods in the clinical setting is discussed by presenting the assumptions and limitations associated with each method that may assist the clinician in characterizing the health and nutritional status of the fetus, infant and child. It is our hope that this review will help guide future research efforts directed at increasing the understanding of how body composition in early development may be associated with chronic diseases in later life.

Maternal fat mass at mid-pregnancy and birth weight in Brazilian women

BACKGROUND

The relationship between maternal body composition and foetal development is unclear.

AIM

To determine the relationship between maternal body composition [fat mass (FM) and fat-free mass (FFM)] and foetal growth and birth weight, independent of potential confounding factors.

SUBJECTS AND METHODS

This study consisted of 92 women, normal and overweight/obese, recruited from the Instituto Fernandes Figueira in Rio de Janeiro, Brazil. Body composition (FM and FFM) was estimated using bioelectrical impedance. Foetal growth was assessed using serial ultrasound measurements at the second and third trimester and infant's weight and length were measured at birth. Multiple linear regression analyses were used to determine the association between maternal FM and FFM and birth weight adjusted for gestational age (BWt) and change in estimated foetal weight (ΔEFW), controlling for infant gender, maternal serum glucose, energy intake, parity, height and income.

RESULTS

Maternal FM, but not FFM, was positively associated with BWt (p = 0.02) and borderline with ΔEFW (p = 0.05). FM expressed as a percentage of body weight (%FM) showed a significant positive association with BWt (p < 0.001) and ΔEFW (p < 0.01). Using backward linear regression analysis, FM was a significant predictor of BWt (p < 0.001) and ΔEFW (p = 0.03), but not change in femur length.

CONCLUSION

In this small sample of normal and overweight/obese women, maternal FM at mid-pregnancy is associated with neonatal BW and foetal growth.

The association between portion size, nutrient intake and gestational weight gain: a secondary analysis in the WATCH study 2006/7

BACKGROUND

Excessive gestational weight gain (GWG) is associated with adverse maternal-child health outcomes. Managing energy intake and GWG versus optimising nutrient intake can be challenging. The present study aimed to examine the relationships between dietary portion size, GWG and nutrient intakes during pregnancy. It is hypothesised that, after adjustment for potential confounders, portion size would be positively associated with both GWG and nutrient intakes during pregnancy.

METHODS

Prospective data were obtained for 179 Australian women from the Women and Their Children's Health Study. A validated food frequency questionnaire was used at 18-24 and 36-40 weeks of gestation to quantify diet and portion size during the previous 3 months of pregnancy. Nutrient intakes were compared with Australian Nutrient Reference Values (NRVs). GWG was measured up to 36 weeks and compared with the Institute of Medicine weight gain recommendations (WtAdh).

RESULTS

In multivariate regression models, portion size factor (PSF) was positively associated with GWG in women with high socio-economic status (SES; β = 0.20, P = 0.04) and those with an overweight/obese pre-pregnancy body mass index (BMI) (β = 0.28, P = 0.04). PSF uniquely accounted for 8.2% and 3.7% of the variability in GWG for women with high SES and overweight/obese pre-pregnancy BMIs, respectively. Nutrient intakes and PSF were similar regardless of WtAdh. Women achieved NRVs for calcium and zinc in all PSF categories. Most of the women with large PSF still failed to achieve the NRVs for folate (95.7%), iron (89.6%) and fibre (85.5%).

CONCLUSIONS

All women require advice on quality food choices during pregnancy to optimise health outcomes. Targeting portion size alone is insufficient to manage GWG but may prove to be a valuable tool in pregnant women of high SES and/or those who are overweight/obese pre-pregnancy.

Lower Protein-to-Carbohydrate Ratio in Maternal Diet is Associated with Higher Childhood Systolic Blood Pressure up to Age Four Years

The prenatal environment can influence development of offspring blood pressure (BP), which tracks into adulthood. This prospective longitudinal study investigated whether maternal pregnancy dietary intake is associated with the development of child BP up to age four years. Data are from 129 mother-child dyads enrolled in the Women and Their Children's Health study. Maternal diet was assessed using a validated 74-item food frequency questionnaire at 18 to 24 weeks and 36 to 40 weeks, with a reference period of the previous three months. Child systolic and diastolic BP were measured at 3, 6, 9, 12, 24, 36 and 48 months, using an automated BP monitor. Using mixed-model regression analyses adjusted for childhood growth indices, pregnancy intakes of percentage of energy (E%) polyunsaturated fat (β coefficient 0.73; 95% CI 0.003, 1.45; p = 0.045), E% omega-6 fatty acids (β coefficient 0.89; 95% CI 0.09, 1.69; p = 0.03) and protein-to-carbohydrate (P:C) ratio (β coefficient -14.14; 95% CI -27.68, -0.60; p = 0.04) were associated with child systolic BP trajectory up to 4 years. Child systolic BP was greatest at low proportions of dietary protein (<16% of energy) and high carbohydrate (>40% of energy) intakes. There may be an ideal maternal macronutrient ratio associated with optimal infant BP. Maternal diet, which is potentially modifiable, may play an important role in influencing offspring risk of future hypertension.

Longitudinal changes in gestational weight gain and the association with intrauterine fetal growth

OBJECTIVE

Total pregnancy weight gain has been associated with infant birthweight; however, most prior studies lacked repeat ultrasound measurements. Understanding of the longitudinal changes in maternal weight gain and intrauterine changes in fetal anthropometrics is limited.

STUDY DESIGN

Prospective data from 1314 Scandinavian singleton pregnancies at high-risk for delivering small-for-gestational-age (SGA) were analyzed. Women had ≥1 (median 12) antenatal weight measurements. Ultrasounds were targeted at 17, 25, 33, and 37 weeks of gestation. Analyses involved a multi-step process. First, trajectories were estimated across gestation for maternal weight gain and fetal biometrics [abdominal circumference (AC, mm), biparietal diameter (BPD, mm), femur length (FL, mm), and estimated fetal weight (EFW, g)] using linear mixed models. Second, the association between maternal weight changes (per 5 kg) and corresponding fetal growth from 0 to 17, 17 to 28, and 28 to 37 weeks was estimated for each fetal parameter adjusting for prepregnancy body mass index, height, parity, chronic diseases, age, smoking, fetal sex, and weight gain up to the respective period as applicable. Third, the probability of fetal SGA, EFW <10th percentile, at the 3rd ultrasound was estimated across the spectrum of maternal weight gain rate by SGA status at the 2nd ultrasound.

RESULTS

From 0 to 17 weeks, changes in maternal weight were most strongly associated with changes in BPD [β=0.51 per 5 kg (95%CI 0.26, 0.76)] and FL [β=0.46 per 5 kg (95%CI 0.26, 0.65)]. From 17 to 28 weeks, AC [β=2.92 per 5 kg (95%CI 1.62, 4.22)] and EFW [β=58.7 per 5 kg (95%CI 29.5, 88.0)] were more strongly associated with changes in maternal weight. Increased maternal weight gain was significantly associated with a reduced probability of intrauterine SGA; for a normal weight woman with SGA at the 2nd ultrasound, the probability of fetal SGA with a weight gain rate of 0.29 kg/w (10th percentile) was 59%, compared to 38% with a rate of 0.67 kg/w (90th percentile).

CONCLUSION

Among women at high-risk for SGA, maternal weight gain was associated with fetal growth throughout pregnancy, but had a differential relationship with specific biometrics across gestation. For women with fetal SGA identified mid-pregnancy, increased antenatal weight gain was associated with a decreased probability of fetal SGA approximately 7 weeks later.

Maternal diet but not gestational weight gain predicts central adiposity accretion in utero among pregnant adolescents

BACKGROUND

Modifiable risk factors during pregnancy, such as diet and weight gain, are associated with fetal birth weight but little is known about how these factors influence fetal fat acquisition in utero among pregnant adolescents.

OBJECTIVE

To determine whether maternal pre-pregnancy BMI (ppBMI), gestational weight gain (GWG) and dietary intake during pregnancy influence fetal fat accretion in utero.

METHODS

Longitudinal data were obtained from 121 pregnant adolescents enrolled in a study designed to identify determinants of maternal and fetal bone changes across gestation. Adolescents (ages 13-18 years) completed up to three study visits during early, mid- and late gestation. Maternal anthropometrics, 24 h dietary recalls and measures of fetal biometry were obtained at each visit. Fetal abdominal wall thickness (abdominal subcutaneous fat thickness, AbFat), a measure of fetal subcutaneous fat, was calculated by sonography at each visit. Statistical determinants of AbFat during late pregnancy were explored using simple and multiple regression.

RESULTS

During late pregnancy (34.8±2.0 weeks; range 31.0-40.6 weeks of gestation), the median (inter-quartile range) fetal AbFat and GWG were 0.44 (0.39, 0.55) cm and 14.6 (9.5, 18.3) kg, respectively. After adjusting for infant birth weight, variables significantly associated with fetal AbFat included gestational age (P<0.0001, 95% confidence interval, CI: 0.01, 0.03), maternal race (P=0.029, 95% CI: -0.04, -0.002) and dietary intake of added sugar (P=0.025, 95% CI: 1.42e-6, 2.06e-5). Fetal AbFat had a significant positive quadratic relationship with total maternal dietary sugar intake such that both low and high extremes of sugar consumption were associated with significantly higher fetal AbFat. Birth weight was not significantly associated with maternal intake of added sugars.

CONCLUSION

Extreme sugar intakes among pregnant adolescents may lead to increased accumulation of fetal abdominal fat with little net effect on birth weight. This finding suggests that increased sugar consumption during pregnancy promotes shifts in fetal body composition.

Maternal diet during early childhood, but not pregnancy, predicts diet quality and fruit and vegetable acceptance in offspring

Studies have identified prenatal flavour exposure as a determinant of taste preferences in infants; however, these studies have focused on relatively small samples and limited flavours. As many parents struggle with getting children to accept a variety of nutritious foods, a study of the factors influencing food acceptance is warranted. The objective of this study was to determine whether exposure to a wider variety of fruit and vegetables and overall higher diet quality in utero results in acceptance of a greater variety of these foods and better diet quality for offspring during childhood. This study is a secondary data analysis of pregnant women (n = 52) and their resulting offspring recruited for the Women and Their Children's Health study in NSW, Australia. Dietary intake of mothers and children was measured using food frequency questionnaires. Diet quality and vegetable and fruit variety were calculated using the Australian Recommended Food Score and the Australian Child and Adolescent Recommended Food Score. Associations between maternal and child diet quality and variety were assessed using Pearson's correlations and the total effect of in utero maternal pregnancy diet on childhood diet was decomposed into direct and indirect effect using mediation analysis. Maternal pregnancy and post-natal diet were both correlated with child diet for overall diet quality and fruit and vegetable variety (P < 0.001). Mediation analyses showed that the indirect effect of maternal pregnancy diet on child diet was mediated through maternal post-natal diet, particularly for fruit (P = 0.045) and vegetables (P = 0.055). Nutrition intervention should therefore be aimed at improving diet quality and variety in mothers with young children, in order to subsequently improve eating habits of offspring.

The association between the macronutrient content of maternal diet and the adequacy of micronutrients during pregnancy in the Women and Their Children’s Health (WATCH) study

Nutrition during pregnancy can induce alterations in offspring phenotype. Maternal ratio of protein to non-protein (P:NP) energy has been linked to variations in offspring body composition and adult risk of metabolic disease. This study describes the dietary patterns of pregnant women by tertiles of the P:NP ratio and compares diet to Australian recommendations. Data are from 179 Australian women enrolled in the Women and Their Children's Health Study. Diet was assessed using a validated 74-item food frequency questionnaire. Food group servings and nutrient intakes were compared to the Australian Guide to Healthy Eating and Australian Nutrient Reference Values. Higher maternal P:NP tertile was positively associated with calcium (P = 0.003), zinc (P = 0.001) and servings of dairy (P = 0.001) and meat (P = 0.001) food groups, and inversely associated with the energy dense, nutrient poor non-core (P = 0.003) food group. Micronutrient intakes were optimized with intermediate protein (18%E-20%E), intermediate fat (28%E-30%E) and intermediate carbohydrate (50%E-54%E) intakes, as indicated in tertile two. Results suggest a moderate protein intake may support pregnant women to consume the largest variety of nutrients across all food groups.

Dietary balance during pregnancy is associated with fetal adiposity and fat distribution

BACKGROUND

The prenatal environment can induce permanent changes in offspring phenotype. Thinness at birth is associated with adult risk of cardiometabolic disease.

OBJECTIVE

The objective was to investigate the association between maternal nutrition during pregnancy and intrauterine development of fetal body composition.

DESIGN

We used prospective data from 179 Australian women with singleton pregnancies from the Women and Their Children's Health Study. A validated food-frequency questionnaire was used at 18-24 wk and 36-40 wk of gestation to quantify maternal diet during the previous 3 mo of pregnancy. Fetal body-composition measurements were ascertained from abdominal and midthigh sites by ultrasound performed at 19, 25, 30, and 36 wk. The subcutaneous fat area at each site was calculated by subtracting the lean/visceral area from the total area.

RESULTS

In linear mixed-model regressions, maternal intakes of protein (b = -0.13; P = 0.04) and starch (b = 0.10; P = 0.02) and the protein:carbohydrate ratio (b = -3.61; P = 0.02) were associated with the percentage of abdominal fat, whereas SFA (b = 0.27; P = 0.04) and PUFA (b = -0.48; P = 0.03) were associated with the percentage of midthigh fat. Response surfaces for fetal adiposity were maximized at different macronutrient intakes. Abdominal fat was highest with low protein intakes (<16% of energy), and midthigh fat was highest at intermediate protein (18-21% of energy), high fat (>40% of energy), and low carbohydrate (<40% of energy) intakes.

CONCLUSION

Fetal body composition may be modifiable via nutritional intervention in the mother and thus may play an important role in influencing the offspring's risk of future disease.

Protocol for the Women And Their Children's Health (WATCH) study: a cohort of pregnancy and beyond

BACKGROUND

The developmental origins of health and disease is a conceptual framework that helps explain the links between our early life exposures and later health outcomes, and is a burgeoning field of research. In this report, we describe the study protocol used in a prospective cohort of women recruited during pregnancy, with postnatal follow-up of the mothers and offspring.

METHODS

The Women And Their Children's Health (WATCH) cohort (n = 180 women) is being conducted at the John Hunter Hospital, Australia (from June 2006). Women attended study visits during pregnancy at 19, 24, 30, and 36 weeks' gestation. Postnatal follow-up of the women and their offspring occurred at 3-month intervals during the first year after birth and annually thereafter, until age 4 years. Fetal ultrasound scans were performed at each pregnancy visit. Pregnancy and birth data were obtained from hospital records. Data collection has included maternal and child anthropometric, biochemical, dietary, physical activity, socioeconomic, medical, and other variables.

CONCLUSIONS

The 2 most novel components of our prospective cohort study are (1) the regular and systematic tracking of fetal and child growth and body composition, starting in the second trimester of pregnancy and continuing to age 4 years, and (2) the detailed maternal and child dietary data collection, including biochemical parameters. Detailed cohorts that collect data on the early nutritional, physiological, and social determinants of health are valuable. Despite its relatively small sample size, many hypotheses on developmental origins can be tested or piloted using data collected from the WATCH cohort.