Maternal Vitamin C Intake during Pregnancy Influences Long-Term Offspring Growth with Timing- and Sex-Specific Effects in Guinea Pigs

Our previous work in guinea pigs revealed that low vitamin C intake during preconception and pregnancy adversely affects fertility, pregnancy outcomes, and foetal and neonatal growth in a sex-dependent manner. To investigate the long-term impact on offspring, we monitored their growth from birth to adolescence (four months), recorded organ weights at childhood equivalence (28 days) and adolescence, and assessed physiological parameters like oral glucose tolerance and basal cortisol concentrations. We also investigated the effects of the timing of maternal vitamin C restriction (early vs. late gestation) on pregnancy outcomes and the health consequences for offspring. Dunkin Hartley guinea pigs were fed an optimal (900 mg/kg feed) or low (100 mg/kg feed) vitamin C diet ad libitum during preconception. Pregnant dams were then randomised into four feeding regimens: consistently optimal, consistently low, low during early pregnancy, or low during late pregnancy. We found that low maternal vitamin C intake during early pregnancy accelerated foetal and neonatal growth in female offspring and altered glucose homeostasis in the offspring of both sexes at an age equivalent to early childhood. Conversely, low maternal vitamin C intake during late pregnancy resulted in foetal growth restriction and reduced weight gain in male offspring throughout their lifespan. We conclude that altered vitamin C during development has long-lasting, sex-specific consequences for offspring and that the timing of vitamin C depletion is also critical, with low levels during early development being associated with the development of a metabolic syndrome-related phenotype, while later deprivation appears to be linked to a growth-faltering phenotype.

Reconsidering the developmental origins of adult disease paradigm: The 'metabolic coordination of childbirth' hypothesis

In uncomplicated pregnancies, birthweight is inversely associated with adult non-communicable disease (NCD) risk. One proposed mechanism is maternal malnutrition during pregnancy. Another explanation is that shared genes link birthweight with NCDs. Both hypotheses are supported, but evolutionary perspectives address only the environmental pathway. We propose that genetic and environmental associations of birthweight with NCD risk reflect coordinated regulatory systems between mother and foetus, that evolved to reduce risks of obstructed labour. First, the foetus must tailor its growth to maternal metabolic signals, as it cannot predict the size of the birth canal from its own genome. Second, we predict that maternal alleles that promote placental nutrient supply have been selected to constrain foetal growth and gestation length when fetally expressed. Conversely, maternal alleles that increase birth canal size have been selected to promote foetal growth and gestation when fetally expressed. Evidence supports these hypotheses. These regulatory mechanisms may have undergone powerful selection as hominin neonates evolved larger size and encephalisation, since every mother is at risk of gestating a baby excessively for her pelvis. Our perspective can explain the inverse association of birthweight with NCD risk across most of the birthweight range: any constraint of birthweight, through plastic or genetic mechanisms, may reduce the capacity for homeostasis and increase NCD susceptibility. However, maternal obesity and diabetes can overwhelm this coordination system, challenging vaginal delivery while increasing offspring NCD risk. We argue that selection on viable vaginal delivery played an over-arching role in shaping the association of birthweight with NCD risk.

The clinical performance and population health impact of birthweight-for-gestational age indices at term gestation

BACKGROUND

The assessment of birthweight for gestational age and the identification of small- and large-for-gestational age (SGA and LGA) infants remain contentious, despite the recent creation of the Intergrowth 21st Project and World Health Organisation (WHO) birthweight-for-gestational age standards.

OBJECTIVE

We carried out a study to identify birthweight-for-gestational age cut-offs, and corresponding population-based, Intergrowth 21st and WHO centiles associated with higher risks of adverse neonatal outcomes, and to evaluate their ability to predict serious neonatal morbidity and neonatal mortality (SNMM) at term gestation.

METHODS

The study population was based on non-anomalous, singleton live births between 37 and 41 weeks' gestation in the United States from 2003 to 2017. SNMM included 5-min Apgar score <4, neonatal seizures, need for assisted ventilation, and neonatal death. Birthweight-specific SNMM was modelled by gestational week using penalised B-splines. The birthweights at which SNMM odds were minimised (and higher by 10%, 50% and 100%) were estimated, and the corresponding population, Intergrowth 21st, and WHO centiles were identified. The clinical performance and population impact of these cut-offs for predicting SNMM were evaluated.

RESULTS

The study included 40,179,663 live births and 991,486 SNMM cases. Among female singletons at 39 weeks' gestation, SNMM odds was lowest at 3203 g birthweight, and 10% higher at 2835 g and 3685 g (population centiles 11th and 82nd, Intergrowth centiles 17th and 88th and WHO centiles 15th and 85th). Birthweight cut-offs were poor predictors of SNMM, for example, the cut-offs associated with 10% and 50% higher odds of SNMM among female singletons at 39 weeks' gestation resulted in a sensitivity, specificity, and population attributable fraction of 12.5%, 89.4%, and 2.1%, and 2.9%, 98.4% and 1.3%, respectively.

CONCLUSIONS

Reference- and standard-based birthweight-for-gestational age indices and centiles perform poorly for predicting adverse neonatal outcomes in individual infants, and their associated population impact is also small.

Maternal Prepregnancy Obesity Affects Foetal Growth, Birth Outcome, Mode of Delivery, and Miscarriage Rate in Austrian Women

The increasing obesity rates among women of reproductive age create a major obstetrical problem as obesity during pregnancy is associated with many complications, such as a higher rate of caesarean sections. This medical record-based study investigates the effects of maternal prepregnancy obesity on newborn parameters, birth mode, and miscarriage rate. The data of 15,404 singleton births that had taken place between 2009 and 2019 at the public Danube Hospital in Vienna were enrolled in the study. Newborn parameters are birth weight, birth length, head circumference, APGAR scores, as well as pH values of the arterial and venous umbilical cord blood. In addition, maternal age, height, body weight at the beginning and the end of pregnancy, and prepregnancy body mass index (BMI) (kg/m²) have been documented. The gestational week of birth, the mode of delivery, as well as the number of previous pregnancies and births, are included in the analyses. Birth length, birth weight, and head circumference of the newborn increase with increasing maternal BMI. Furthermore, with increasing maternal weight class, there tends to be a decrease in the pH value of the umbilical cord blood. Additionally, obese women have a history of more miscarriages, a higher rate of preterm birth, and a higher rate of emergency caesarean section than their normal-weight counterparts. Consequently, maternal obesity before and during pregnancy has far-reaching consequences for the mother, the child, and thus for the health care system.

MicroRNA-185-5p: a marker of brain-sparing in foetuses with late-onset growth restriction

To compare the expression of microRNA-185-5p (miR-185-5p) in normal foetuses and in foetuses with late-onset growth restriction (FGR) and to determine the factors influencing this expression. In a prospective study, 40 foetuses (22 of them with late-onset FGR and 18 with normal growth) were scanned with Doppler ultrasound after week 35 and followed until birth. Subsequently, blood samples from umbilical cords were collected after delivery to evaluate the expression of miR-185-5p using real-time qPCR. Finally, multivariable regression analysis was applied to determine the clinical and ultrasonographic factors influencing miR-185-5p expression in both normal and late-onset FGR foetuses. In comparison with normal foetuses, late-onset FGR foetuses expressed upregulation of miR-185-5p (2.26 ± 1.30 versus 1.27 ± 1.03 2^-ddCt, P = 0.011). Multivariable regression analysis confirmed that cerebroplacental ratio (P < 0.05) was the only determinant of this overexpression. FGR foetuses overexpress miR-185-5p in relation to brain-sparing. Future studies will be needed to investigate the role of miR-185 in the management of late-onset FGR.

A United States national reference for foetal growth for Asian American ethnicities

The purpose of this study was to calculate 10th, 50th, and 90th percentiles of birth weight for gestational age for the total US population and the Asian-American ethnicities. Using the US Natality data files for the years 1992-2020, estimated growth curves were determined across gestational ages and for each Asian American ethnic group-Chinese, Asian Indians, Japanese, Koreans, Filipino, and Vietnamese. Average weight at the 10th, 50th and 90th foetal growth percentiles by race/ethnicity and sex were calculated. Overall, for the 10th, 50th and 90th percentiles, Asian American average birth weight was 18, 90 and 144 g lower than the national average, respectively. We also found that Asian Indians consistently had the lowest birthweight, while Koreans had the highest birthweight among Asian Americans. Updated racial/ethnic-specific weight percentiles by gestational age can be a useful reference for accurate small and large-for-gestational age classifications among different Asian American sub-populations.Impact statementWhat is already known on this subject? Foetal growth is an important determinant of infants' immediate and long-term health outcomes and foetal growth reference curves have been developed to provide average birth weights for each week of gestation and identify growth-restricted as well as excess-weighing foetuses.What the results of this study add? Using the U.S. Natality data files for the years 1992-2020, estimated growth curves were determined across gestational ages and for each Asian American ethnic group-Chinese, Asian Indians, Japanese, Koreans, Filipino, and Vietnamese. Average weight at the 10th, 50th and 90th foetal growth percentiles by race/ethnicity and sex were calculated.What the implications are of these findings for clinical practice and/or further research? Updated racial/ethnic-specific weight percentiles by gestational age can be a useful reference for accurate small and large-for-gestational age classifications among different Asian American sub-groups.

Conditional standards for the quantification of foetal growth in an ethnic Chinese population: a longitudinal study

This was an observational study of low-risk singleton pregnancies in an ethnic Chinese population. Foetal biometric variables which included biparietal diameter (BPD), head circumference (HC), abdominal circumference (AC) and femur length (FL) were measured repeatedly. The standard views for measurement were obtained according to INTERGROWTH-21st criteria. A linear mixed model with fractional polynomial regression was used to describe the longitudinal design. The study included 1289 foetuses and a total of 5125 ultrasound scans, of which each foetus was scanned at least three times, the intervals between scans being at least two weeks. The parameters of the linear mixed models were estimated by Stata v.16 (College Station, TX). Using these parameters, the equations of the mean and variance for BPD, HC, AC and FL were constructed. The conditional percentiles or Z scores could be calculated based on the above equations and previous measurements of the same foetus. A spreadsheet was provided for implementation.Impact StatementWhat is already known on this subject? Longitudinal data derived from serial measurements are therefore appropriate for assessing both foetal size and foetal growth. At present, most reference charts of ethnic Chinese foetal biometry are derived from cross-sectional data, which can only assess foetal size.What do the results of this study add? In this study, we have constructed conditional standards for foetal biometry in an ethnic Chinese population and provided a spreadsheet for querying.What are the implications of these findings for clinical practice and/or further research? The conditional standards can be used to assess foetal growth in clinical practice. In the future, we hope that these foetal growth standards can be applied to determine whether abnormal growth increases the risk of adverse outcomes.

Associations of maternal and infant metabolite profiles with foetal growth and the odds of adverse birth outcomes

BACKGROUND

Adaptations in maternal and foetal metabolic pathways may predispose to altered foetal growth and adverse birth outcomes.

OBJECTIVE

To assess the associations of maternal early-pregnancy metabolite profiles and infant metabolite profiles at birth with foetal growth from first trimester onwards and the odds of adverse birth outcomes.

METHODS

In a prospective population-based cohort among 976 Dutch pregnant women and their children, serum concentrations of amino acids, non-esterified fatty acids (NEFA), phospholipids (PL) and carnitines in maternal early-pregnancy blood and in cord blood were obtained by liquid-chromatography tandem mass spectrometry. Information on foetal growth was available from first trimester onwards.

RESULTS

After false discovery rate correction for multiple testing, higher infant total and individual NEFA concentrations were associated with a lower weight, length, and head circumference at birth. Higher infant total and individual acyl-lysophosphatidylcholine (lyso.PC.a) and alkyl-lysophosphatidylcholine concentrations were associated with higher weight and head circumference (lyso.PC.a only) at birth, higher odds of LGA and lower odds of SGA. Few individual maternal metabolites were associated with foetal growth measures in third trimester and at birth, but not with the odds of adverse birth outcomes.

CONCLUSIONS

Our results suggest that infant metabolite profiles, particularly total and individual lyso.PC.a and NEFA concentrations, were strongly related to growth measures at birth and the odds of adverse birth outcomes. Few individual maternal early-pregnancy metabolites, but not total metabolite concentrations, are associated with foetal growth measures in third trimester and at birth.

Prenatal antibiotic exposure and birth weight

BACKGROUND/OBJECTIVES

Current research suggests an association between antibiotic use in early life and later obesity. Less is known about prenatal antibiotic exposure and foetal growth. We investigated the association between prenatal antibiotic exposure and birth weight.

METHODS

Data from the Danish National Birth Cohort were linked to the Danish National Medical Birth Registry. Exposure was self-reported antibiotic use in pregnancy. Outcome was registered birth weight. Multivariable linear regression models were adjusted for confounders defined a priori.

RESULTS

A total of 63 300 mother-child dyads from 1996 to 2002 were included. Overall, prenatal antibiotic exposure was not associated with birth weight (-8.90 g, 95%CI: -19.5- +1.64 g, p = 0.10). Findings were similar for those born term and preterm. Antibiotic exposure in second to third trimester, compared to no exposure, was associated with lower birth weight (-12.6 g, 95%CI: -24.1 to -1.1 g, p = 0.03). In sex-stratified analyses, there were no observed associations between antibiotics and birth weight. With further stratifications, prenatal antibiotic exposure and birth weight were associated in boys who were preterm (+91.0 g, 95%CI: +6.8 g- +175.2 g, p = 0.03) but not among girls who were preterm (-44.0 g, 95%CI: -128.1 to +40.0 g, p = 0.30).

CONCLUSIONS

Prenatal antibiotic exposure is not consistently associated with birth weight.

Infants' prenatal exposure to opioids and the association with birth outcomes: A systematic review and meta-analysis

BACKGROUND

Prenatal exposure to opioids (PEO) is a worldwide public health issue. Opioids cross the placental barrier and may affect the developing foetus and the birth outcomes.

OBJECTIVES

This review aimed to explore newborns' weight, length and head circumference, preterm birth, and perinatal death as primary outcomes in relation to PEO. The secondary outcomes were gestational age at birth, Apgar scores and length of hospitalisation after delivery.

DATA SOURCES

PubMed, Embase, PsycInfo and the Web of Science.

STUDY SELECTION AND DATA EXTRACTION

Inclusion criteria were (i) cohort, case-control or cross-sectional peer-reviewed studies published in English through 1 March 2021; (ii) comparing outcomes between prenatal exposed and unexposed groups to opioids (prescribed or obtained illegally). Exclusion criteria were foetal alcohol syndrome and non-opioid primary exposure.

SYNTHESIS

Data were extracted by two authors. The Newcastle-Ottawa Quality Assessment Scale was used for study quality assessment. Due to heterogeneity across studies, we used random effects models to obtain pooled standardised mean difference (SMD), pooled risk ratio (RR) and 95% confidence interval (CI).

RESULTS

Data from 80 studies were extracted. In meta-analyses, opioid-exposed neonates had lower birthweight (SMD -0.77, 95% CI -0.90, -0.64, I²  = 82%), smaller head circumference (SMD -0.67, 95% CI -0.86, -0.48, I²  = 84%), shorter birth length (SMD -0.97, 95% CI -1.24, -0.70, I²  = 91%) and gestational age (SMD -0.45, 95% CI -0.60, -0.30, I²  = 80%) than unexposed neonates. Pooled risks of neonatal death and preterm birth were higher among opioid-exposed compared to unexposed neonates (RR 4.05, 95% CI 2.12, 7.72, I²  = 73%; and RR 1.92, 95% CI 1.57, 2.35, I²  = 99%).

CONCLUSIONS

We found increased risks of adverse birth outcomes in relation to PEO. Caution should be used in interpreting the findings, as many studies were rated as poor quality, and with substantial inter-study heterogeneity. Future studies should ensure comparability of opioid-exposed and -unexposed group to strengthen internal validity.

Birth weight for gestational age and later cardiovascular health: a comparison between longitudinal Finnish and indigenous Australian cohorts

INTRODUCTION

Small or large birth weight for gestational age has been linked with later cardiovascular disease risk. However, cardiovascular risk markers from childhood to adulthood according to birth weight in diverse longitudinal settings globally have not been extensively studied.

OBJECTIVES

To examine the relationship between birth weight and cardiovascular risk profile from childhood until young adulthood in two geographically and socioeconomically distinct cohorts.

METHODS

Data were derived from two longitudinal birth cohort studies; one from southern Finland (Special Turku Coronary Risk Factor Intervention Project, STRIP) and one from northern Australia comprising Indigenous Australians (Aboriginal Birth Cohort, ABC). The sample included 747 Finnish participants and 541 Indigenous Australians with data on birth weight, gestational age and cardiovascular risk factors (body mass index [BMI]), waist-to-height ratio [WHtR], lipid profile, blood pressure) collected at ages 11, 18 and 25 or 26 years. Carotid intima-media thickness (cIMT) was assessed at age 18 or 19 years. Participants were categorised according to birth weight for gestational age (small [SGA], appropriate [AGA] or large [LGA]). Associations between birth weight category and cardiovascular risk markers were studied using a repeated measures ANOVA.

RESULTS

Higher birth weight category was associated with higher BMI later in life in both cohorts (p=.003 for STRIP and p<.0001 for ABC). In the ABC, higher birth weight category was also associated with higher WHtR (p=.004). In the ABC, SGA participants had lower systolic and diastolic blood pressure than AGA participants (p=.028 for systolic, p=.027 for diastolic) and lower systolic blood pressure than LGA participants (p=.046) at age 25. In the STRIP cohort, SGA participants had lower cIMT than LGA participants (p=.024).

CONCLUSIONS

Birth weight can predict future cardiovascular risk profile in diverse populations. Thus, it needs to be included in targeted public health interventions for tackling the obesity pandemic and improving cardiovascular health worldwide.Key messagesThe strongest association between birth weight and later cardiovascular risk profile was manifested as differences in body mass index in two culturally and geographically distinct cohorts.Foetal growth is a determinant for later cardiovascular health in diverse populations, indicating a need to focus on maternal and foetal health to improve cardiovascular health worldwide.

In utero substrate restriction by placental insufficiency or maternal undernutrition decreases optical redox ratio in foetal perirenal fat

Intrauterine growth restriction (IUGR) can result from reduced delivery of substrates, including oxygen and glucose, during pregnancy and may be caused by either placental insufficiency or maternal undernutrition. As a consequence of IUGR, there is altered programming of adipose tissue and this can be associated with metabolic diseases later in life. We have utilised two sheep models of IUGR, placental restriction and late gestation undernutrition, to determine the metabolic effects of growth restriction on foetal perirenal adipose tissue (PAT). Two-photon microscopy was employed to obtain an optical redox ratio, which gives an indication of cell metabolism. PAT of IUGR foetuses exhibited higher metabolic activity, altered lipid droplet morphology, upregulation of cytochrome c oxidase subunit genes and decreased expression of genes involved in growth and differentiation. Our results indicate that there are adaptations in PAT of IUGR foetuses that might be protective and ensure survival in response to an IUGR insult.

Adiponectin as a Potential Biomarker for Pregnancy Disorders

Adiponectin is an adipocyte-derived hormone that plays a critical role in energy homeostasis, mainly attributed to its insulin-sensitizing properties. Accumulating studies have reported that adiponectin concentrations are decreased during metabolic diseases, such as obesity and type 2 diabetes, with an emerging body of evidence providing support for its use as a biomarker for pregnancy complications. The identification of maternal factors that could predict the outcome of compromised pregnancies could act as valuable tools that allow the early recognition of high-risk pregnancies, facilitating close follow-up and prevention of pregnancy complications in mother and child. In this review we consider the role of adiponectin as a potential biomarker of disorders associated with pregnancy. We discuss common disorders associated with pregnancy (gestational diabetes mellitus, preeclampsia, preterm birth and abnormal intrauterine growth) and highlight studies that have investigated the potential of adiponectin to serve as biomarkers for these disorders. We conclude the review by recommending strategies to consider for future research.

Temporal relationships between maternal metabolic parameters with neonatal adiposity in women with obesity differ by neonatal sex: Secondary analysis of the DALI study

OBJECTIVES

To investigate the importance of time in pregnancy and neonatal sex on the association between maternal metabolic parameters and neonatal sum of skinfolds.

METHODS

This was a longitudinal, secondary analysis of the vitamin D and lifestyle intervention for gestational diabetes mellitus study, conducted in nine European countries during 2012 to 2015. Pregnant women with a pre-pregnancy body mass index (BMI) of ≥29 kg/m² were invited to participate. We measured 14 maternal metabolic parameters at three times during pregnancy: <20 weeks, 24 to 28 weeks, and 35 to 37 weeks of gestation. The sum of four skinfolds assessed within 2 days after birth was the measure of neonatal adiposity.

RESULTS

In total, 458 mother-infant pairs (50.2% female infants) were included. Insulin resistance (fasting insulin and HOMA-index of insulin resistance) in early pregnancy was an important predictor for boys' sum of skinfolds, in addition to fasting glucose and maternal adiposity (leptin, BMI and neck circumference) throughout pregnancy. In girls, maternal lipids (triglycerides and fatty acids) in the first half of pregnancy were important predictors of sum of skinfolds, as well as fasting glucose in the second half of pregnancy.

CONCLUSIONS

Associations between maternal metabolic parameters and neonatal adiposity vary between different periods during pregnancy. This time-dependency is different between sexes, suggesting different growth strategies.

Associations between estimated foetal weight discordance and clinical characteristics within dichorionic twins: The NICHD Fetal Growth Studies

BACKGROUND

Birthweight discordance is well studied, with less known about longitudinal inter-twin differences in foetal growth.

OBJECTIVE

To examine inter-twin per cent differences in EFW (EFW_% ), head (HC_% ) and abdominal circumference (AC_% ), and femur length (FL_% ) across gestation in dichorionic twin gestations and explore associated characteristics.

METHODS

Foetal biometrics were assessed by ultrasound and EFW calculated at ≤6 study visits among women with dichorionic twin pregnancies enrolled in the NICHD Fetal Growth Studies cohort (US, 2012-2013). Inter-twin per cent difference was defined: ([Size_{larger twin}  - Size_{smaller twin} ]/Size_{larger twin}  × 100). Linear mixed models evaluated per cent differences in foetal biometrics at 15 weeks and their change per week overall and by maternal/neonatal characteristics in unadjusted and adjusted models.

RESULTS

In 140 pregnancies, inter-twin per cent differences increased across gestation for EFW (0.18%/week, 95% confidence interval [CI] 0.10, 0.27), HC (0.03%/week, 95% CI 0.00, 0.06), and AC (0.03%/week, 95%CI -0.01, 0.08) but decreased for FL (-0.03%/week, 95% CI -0.09, 0.02). After adjustment, change in EFW_% difference across gestation differed by pre-pregnancy body mass index (BMI [kg/m² ]; underweight [<18.5]; normal weight [18.5-24.9]; overweight [25.0-29.9]; obese [≥30.0]; P_interaction  = .022); and conception method (in vitro fertilisation [IVF], intrauterine insemination, ovulation induction medication, donor egg/embryo, none; P_interaction  = .060). While EFW_% difference increased with normal pre-pregnancy BMI (0.24%/week, 95% CI 0.12, 0.37), little change was noted with pre-pregnancy obesity (0.01%/week, 95% CI -0.15, 0.17). EFW_% difference increased in conceptions without fertility treatments (0.23%/week, 95% CI 0.11, 0.34) but not IVF conceptions (-0.00%/week, 95% CI -0.16, 0.16). Similar patterns of differences across gestation were noted for HC_% by conception method (P_interaction  = .026) and AC_% by pre-pregnancy BMI (P_interaction  = .071); changes in HC_% differed by parity (nulliparous, multiparous; P_interaction  = .004).

CONCLUSIONS

EFW_% difference increased across gestation in dichorionic twins, but remained stable with pre-pregnancy obesity or IVF conception, patterns mirrored for HC and AC. Research is needed to understand pathologic versus physiologic differential twin growth trajectories.

Gestational route to healthy birth (GaRBH): protocol for an Indian prospective cohort study

INTRODUCTION

Pregnancy is characterised by a high rate of metabolic shifts from early to late phases of gestation in order to meet the raised physiological and metabolic needs. This change in levels of metabolites is influenced by gestational weight gain (GWG), which is an important characteristic of healthy pregnancy. Inadequate/excessive GWG has short-term and long-term implications on maternal and child health. Exploration of gestational metabolism is required for understanding the quantitative changes in metabolite levels during the course of pregnancy. Therefore, our aim is to study trimester-specific variation in levels of metabolites in relation to GWG and its influence on fetal growth and newborn anthropometric traits at birth.

METHODS AND ANALYSIS

A prospective longitudinal study is planned (start date: February 2018; end date: March 2023) on pregnant women that are being recruited in the first trimester and followed in subsequent trimesters and at the time of delivery (total 3 follow-ups). The study is being conducted in a hospital located in Bikaner district (66% rural population), Rajasthan, India. The estimated sample size is of 1000 mother-offspring pairs. Information on gynaecological and obstetric history, socioeconomic position, diet, physical activity, tobacco and alcohol consumption, depression, anthropometric measurements and blood samples is being collected for metabolic assays in each trimester using standardised methods. Mixed effects regression models will be used to assess the role of gestational weight in influencing metabolite levels in each trimester. The association of maternal levels of metabolites with fetal growth, offspring's weight and body composition at birth will be investigated using regression modelling.

ETHICS AND DISSEMINATION

The study has been approved by the ethics committees of the Department of Anthropology, University of Delhi and Sardar Patel Medical College, Rajasthan. We are taking written informed consent after discussing the various aspects of the study with the participants in the local language.

Mitochondrial implications in human pregnancies with intrauterine growth restriction and associated cardiac remodelling

Intrauterine growth restriction (IUGR) is an obstetric complication characterised by placental insufficiency and secondary cardiovascular remodelling that can lead to cardiomyopathy in adulthood. Despite its aetiology and potential therapeutics are poorly understood, bioenergetic deficits have been demonstrated in adverse foetal and cardiac development. We aimed to evaluate the role of mitochondria in human pregnancies with IUGR. In a single‐site, cross‐sectional and observational study, we included placenta and maternal peripheral and neonatal cord blood mononuclear cells (PBMC and CBMC) from 14 IUGR and 22 control pregnancies. The following mitochondrial measurements were assessed: enzymatic activities of mitochondrial respiratory chain (MRC) complexes I, II, IV, I + III and II + III, oxygen consumption (cell and complex I‐stimulated respiration), mitochondrial content (citrate synthase [CS] activity and mitochondrial DNA copy number), total ATP levels and lipid peroxidation. Sirtuin3 expression was evaluated as a potential regulator of bioenergetic imbalance. Intrauterine growth restriction placental tissue showed a significant decrease of MRC CI enzymatic activity (P < 0.05) and CI‐stimulated oxygen consumption (P < 0.05) accompanied by a significant increase of Sirtuin3/β‐actin protein levels (P < 0.05). Maternal PBMC and neonatal CBMC from IUGR patients presented a not significant decrease in oxygen consumption (cell and CI‐stimulated respiration) and MRC enzymatic activities (CII and CIV). Moreover, CS activity was significantly reduced in IUGR new‐borns (P < 0.05). Total ATP levels and lipid peroxidation were preserved in all the studied tissues. Altered mitochondrial function of IUGR is especially present at placental and neonatal level, conveying potential targets to modulate obstetric outcome through dietary interventions aimed to regulate Sirtuin3 function.

Maternal Fatty Fish Intake Prior to and during Pregnancy and Risks of Adverse Birth Outcomes: Findings from a British Cohort

Fish is an important source of the essential fatty acids contributing to foetal growth and development, but the evidence linking maternal fatty fish consumption with birth outcomes is inconsistent. In the UK, pregnant women are recommended to consume no more than two 140 g portions of fatty fish per week. This study aimed to investigate the association between fatty fish consumption before and during pregnancy with preterm birth and size at birth in a prospective birth cohort. Dietary intake data were acquired from a cohort of 1208 pregnant women in Leeds, UK (CARE Study) to assess preconception and trimester-specific fatty fish consumption using questionnaires. Multiple 24-h recalls during pregnancy were used to estimate an average fatty fish portion size. Intake was classified as ≤2, >2 portions/week and no fish categories. Following the exclusion of women taking cod liver oil and/or omega-3 supplements, the associations between fatty fish intake with size at birth and preterm delivery (<37 weeks gestation) were examined in multivariable regression models adjusting for confounders including salivary cotinine as a biomarker of smoking status.. The proportion of women reporting any fatty fish intake decreased throughout pregnancy, with the lowest proportion observed in trimester 3 (43%). Mean intakes amongst consumers were considerably lower than that recommended, with the lowest intake amongst consumers observed in the 1st trimester (106 g/week, 95% CI: 99, 113). This was partly due to small portion sizes when consumed, with the mean portion size of fatty fish being 101 g. After adjusting for confounders, no association was observed between fatty fish intake before or during pregnancy with size at birth and preterm delivery.

Can the gap in Aboriginal outcomes be explained by DOHaD

In Australia, there are two distinct populations, each with vastly disparate health outcomes: Aboriginal and Torres Strait Islander People and non-Aboriginal Australians. Aboriginal Australians have significantly higher rates of health and socioeconomic disadvantage, and Aboriginal babies are also more likely to be born low birth weight or growth restricted. The Developmental Origins of Health and Disease (DOHaD) hypothesis advocates that a sub-optimal intrauterine environment, often manifested as diminished foetal growth, during critical periods of foetal development has the potential to alter the risk of non-communicable disease in the offspring. A better understanding of the role of the intrauterine environment and subsequent developmental programming, in response to both transgenerational and immediate stimuli, in Aboriginal Australians remains a relatively unexplored field and may provide insights into the prevailing health disparities between Aboriginal and non-Aboriginal children. This narrative review explores the role of DOHaD in explaining the ongoing disadvantage experienced by Aboriginal People in today's society through a detailed discussion of the literature on the association between foetal growth, as a proxy for the quality of the intrauterine environment, and outcomes in the offspring including perinatal health, early life development and childhood education. The literature largely supports this hypothesis and this review therefore has potential implications for policy makers not only in Australia but also in other countries that have minority and Indigenous populations who suffer disproportionate disadvantage such as the United States, Canada and New Zealand.

Foetal ultrasound measurement imputations based on growth curves versus multiple imputation chained equation (MICE)

BACKGROUND

Ultrasound measures are valuable for epidemiologic studies of risk factors for growth restriction. Longitudinal measurements enable investigation of rates of change and identification of windows where growth is impacted more acutely. However, missing data can be problematic in these studies, limiting sample size, ability to characterise windows of vulnerability, and in some instances creating bias. We sought to compare a parametric linear mixed model (LMM) approach to multiple imputation in this setting with multiple imputation by chained equation (MICE) methodology.

METHODS

Ultrasound scans performed for clinical purposes were abstracted from women in the LIFECODES birth cohort (n = 1003) if they were close in time to three study visits (median 18, 26, and 35 weeks' gestation). We created imputed datasets using LMM and MICE and calculated associations between demographic factors and ultrasound parameters cross-sectionally and longitudinally. Results were compared with a complete-case analysis.

RESULTS

Most participants had ultrasounds at 18 weeks' gestation, and ~50% had measurements at 26 and 35 weeks; 100% had birthweight. Associations between demographic factors and ultrasound measures were similar in magnitude, but more precise, when either imputed datasets were used, compared with a complete-case analysis, in both the cross-sectional or longitudinal analyses.

CONCLUSIONS

MICE, though ignoring the non-linear features of the trajectory and within subject correlation, is able to provide reasonable imputation of foetal growth data when compared to LMM. Because it simultaneously imputes missing covariate data and does not require specification of variance structure as in LMM, MICE may be preferable for imputation in this setting.

Effects of maternal nutrient restriction during early or mid-gestation without realimentation on maternal physiology and foetal growth and development in beef cattle

The aim of this study is to determine the effects of early and mid-gestation nutrient restriction on maternal metabolites and foetal growth. Primiparous Angus cows were synchronized and inseminated with semen from one sire. Dietary treatments were: control to gain 1 kg/week (CON) or 0.55% maintenance energy and CP requirements (nutrient restricted; NR). A subset of dams was fed NR (n=8) or CON (n=8) from days 30 to 110 of gestation. Another group was fed CON (n=8), days 30 to 190; NR (n=7), days 30 to 110 followed by CON days 110 to 190; or CON, (n=7) days 30 to 110 followed by NR days 110 to 190. Cows were harvested at days 110 or 190 of gestation, when foetal measurements and samples were collected. Cows that were NR during days 30 to 110 or 110 to 190 of gestation lost significant BW and body condition score (P<0.001), this was associated with reduced plasma glucose during NR (P<0.002). Foetal weights, empty foetal weights, abdominal and thoracic circumferences were all reduced (P<0.03) in day 110 NR animals. Foetal perirenal adipose as a percentage of empty foetal weight was increased (P=0.01) in NR day 110 female foetuses compared with CON foetus. Maternal serum triglycerides at day 110 of gestation were decreased (P<0.05) in NR dams, whereas foetal serum triglycerides were increased (P<0.05) in response to maternal NR. Foetal weights tended to be reduced (P=0.08) in NR/CON and CON/NR v. CON/CON cattle at day 190 of gestation. Empty foetal weights, abdominal and thoracic circumferences were reduced (P⩽0.03) in NR/CON and CON/NR v. CON/CON cattle. Brain weight as a percentage of empty foetal weight was increased (P<0.001) in NR/CON and CON/NR v. CON/CON cattle. Foetal perirenal adipose as a percentage of empty foetal weight was increased (P=0.003) in NR/CON and CON/NR v. CON/CON cattle. Maternal serum triglycerides at day 190 of gestation were decreased (P<0.05) in association with maternal NR. Foetal serum triglycerides at day 190 of gestation were increased (P<0.05) in response to maternal NR during early gestation but decreased by NR in mid gestation compared with CON foetuses. The data show that maternal nutrient restriction during early or mid-gestation cause's asymmetrical foetal growth restriction, regardless if the restriction is preceded or followed by a period of non-restriction.

Association of prenatal antibiotics with foetal size and cord blood leptin and adiponectin

BACKGROUND

Early postnatal antibiotic use has been shown to promote excess weight gain, but it is unclear whether intrauterine exposure to antibiotics is associated with foetal growth and adiposity. The objective of this study was to examine associations of antibiotic prescription in each trimester of pregnancy with foetal size and adipokine levels at birth.

METHODS

In 2128 pregnant women from the pre-birth Project Viva cohort, from electronic medical records, we estimated antibiotic prescribing by timing during pregnancy. Outcomes were sex-specific birth weight-for-gestational-age z-score (BW/GA-z) and levels of umbilical cord leptin and adiponectin. We used linear regression models adjusted for maternal age, pre-pregnancy body mass index, parity, race/ethnicity, education, smoking during pregnancy, household income and child sex and additionally adjusted cord blood leptin and adiponectin models for gestation length.

RESULTS

Of the 2128 women in our sample, 643 (30.2%) were prescribed with oral antibiotics during pregnancy. Mean (standard deviation) BW/GA-z was 0.17 (0.97), cord blood leptin was 9.0 ng mL-1 (6.6) and cord blood adiponectin was 28.8 ng mL-1 (6.8). Overall, antibiotic prescription in pregnancy was associated with lower BW/GA-z [multivariable adjusted β -0.11; 95% confidence interval {CI} -0.20, -0.01]. In trimester-specific analyses, only second trimester antibiotic prescription was associated with lower BW/GA-z (β -0.23; 95% CI -0.37, -0.08). Overall, antibiotic prescription in pregnancy was not associated with cord blood leptin or adiponectin levels. However, in trimester-specific analyses, third trimester antibiotic prescription was associated with higher cord blood leptin (β 2.28 ng mL-1 ; 95% CI 0.38, 4.17).

CONCLUSIONS

Antibiotics in mid-pregnancy were associated with lower birth weight for gestational age, whereas third trimester antibiotics were associated with higher cord blood leptin.

Effects of maternal folic acid supplementation on gene methylation and being small for gestational age

BACKGROUND

Being small for gestational age (SGA), a foetal growth abnormality, has a long-lasting impact on childhood health. Its aetiology and underlying mechanisms are not well understood. Underlying epigenetic changes of imprinted genes have emerged as a potential pathological pathway because they may be associated with growth, including SGA. As a common methyl donor, folic acid (FA) is essential for DNA methylation, synthesis and repair, and FA supplementation is widely recommended for women planning pregnancy. The present study aimed to investigate the inter-relationships among methylation levels of two imprinted genes [H19 differentially methylated regions (DMRs) and MEST DMRs], maternal FA supplementation and SGA.

METHODS

We conducted a case-control study. Umbilical cord blood was taken from 39 SGA infants and 49 controls whose birth weights are appropriate for gestational age (AGA). DNA methylation levels of H19 and MEST DMRs were determined by an analysis of mass array quantitative methylation.

RESULTS

Statistically significantly higher methylation levels were observed at sites 7.8, 9 and 17.18 of H19 (P = 0.030, 0.016 and 0.050, respectively) in the SGA infants compared to the AGA group. In addition, the association was stronger in male births where the mothers took FA around conception at six H19 sites (P = 0.004, 0.005, 0.048, 0.002, 0.021 and 0.005, respectively).

CONCLUSIONS

Methylation levels at H19 DMRs were higher in SGA infants compared to AGA controls. It appears that the association may be influenced by maternal peri-conception FA supplementation and also be sex-specific.

National curves of foetal growth in singleton foetuses of Greek origin

BACKGROUND

Foetal growth monitoring is an essential component of prenatal care with postnatal impact. The aim of the study was to construct reference ranges for foetal biometric parameters in Greek foetuses and to compare them with previously published models.

MATERIALS AND METHODS

Measurements from 1200 Greek foetuses were used to construct normal curves for biparietal diameter (BPD), occipitofrontal diameter (OFD), head circumference (HC), abdominal circumference (AC), femoral length (FL) and the BPD/FL ratio according to the methodology described by Royston and Wright (1998). The model was validated in a second group of 1200 different foetuses using analysis of the corresponding standardized residuals (z-scores). The z-scores which were derived by our model were compared to those calculated using previously published models from other populations.

RESULTS

BPD, OFD, HC, AC, FL and the BPD/FL ratio are accurately described by simple quadratic equations (R(2) > 0·96 for most of the parameters tested). Statistically significant differences were observed for most of the z-scores when our models were compared to previously published models. Less than 10% of our foetuses were < 5th or > 95th centile of the latter models. About 10% of our foetuses were > 95th centile for FL and HC when the INTERGROWTH-21st formulas were used.

CONCLUSION

We present national foetal biometric references. Using charts from other populations (including INTERGROWTH-21st) may be unrepresentative of local populations and lead to misclassification of foetal growth status.

Is there a correlation between aberrant embryonic crown-rump length growth velocities and subsequent birth weights?

In this study, we tested the hypothesis that anomalous first trimester growth affects birth weight. Four hundred and fifteen women with viable singleton pregnancies at the primary transvaginal scan who had at least two crown rump length (CRL) and birth weight data were included. A linear mixed model was fitted to the Box-Cox transformed CRL values to evaluate the association between the GA and the embryonic growth. For multivariate analysis we included maternal age, height, weight, parity, number of miscarriages, vaginal bleeding, smoking, foetal gender, birth weight, small-for-gestation (SGA) and large-for gestation (LGA) categories at delivery. Smoking appeared to be significant for predicting the initial CRL from the beginning of the pregnancy (p value = 0.013). The SGA foetuses appeared to have slightly slower embryonic growth rates compared to non-SGA (p value = 0.045), after taking into account the effect of smoking on the initial CRL. None of the other variables including subsequent birth weight or LGA category have statistically significant effect on the first trimester embryonic growth curve when tested separately.

Foetal and infant growth patterns, airway resistance and school-age asthma

BACKGROUND AND OBJECTIVE

Preterm birth, low birth weight and rapid infant weight gain are associated with increased risks of asthma symptoms in childhood. The underlying mechanism may include persistently higher airway resistance (Rint). The aim of our study was to examine the associations of longitudinally measured foetal and infant growth characteristics with Rint and asthma outcomes in school-age children.

METHODS

This study was embedded in a population-based prospective cohort study in Rotterdam, The Netherlands. Foetal growth was estimated by ultrasound in the second and third trimesters. Infant growth was measured at birth, 3, 6 and 12 months. At age 6 years, Rint was measured, and information about wheezing and asthma was obtained by questionnaires. The number of subjects per analysis differed per available outcome (3954-5066 subjects).

RESULTS

Longitudinal growth analyses showed that school-age children with increased Rint had lower foetal length growth and weight gain, and lower infant length growth. Children with persistent wheezing until age 6 years and physician-diagnosed asthma had a higher Rint compared with children who never wheezed or without asthma (difference z-scores Rint: 0.58 (0.19, 0.97) and 0.55 (0.15, 0.95), respectively).

CONCLUSION

Rint in school-age children is influenced by foetal growth restriction and is associated with asthma outcomes. See article, page 574.

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.

Trajectories of body mass index amongst children who develop type 2 diabetes as adults

OBJECTIVE

Type 2 diabetes (T2D) is a heterogeneous disorder. The aim of this study was to examine the trajectories of childhood growth associated with T2D.

DESIGN AND SUBJECTS

A total of 13 345 individuals born in Helsinki, Finland between 1934 and 1944 were included in the study. The participants' growth had been recorded in detail during childhood, and 11.7% (n = 1558) had been diagnosed with T2D. We divided the cohort around the median body mass index (BMI) at 11 years. Body composition and glucose tolerance were assessed in a clinical subsample (n = 2003) in adulthood.

RESULTS

Two pathways of growth were associated with T2D. Both began with low weight and BMI at birth. In one, persistent low BMI through infancy was followed by a rapid increase in BMI in childhood. Amongst individuals with a BMI at 11 years above the median value, the odds ratio for T2D associated with a one z-score increase in BMI between 2 and 11 years was 1.31 (95% confidence interval 1.21-1.42, P < 0.001). In the other pathway, low BMI at birth, accompanied by short length at birth, was followed by low BMI in childhood. Most women who developed diabetes followed this trajectory; they developed T2D at a lower BMI and lower fat percentage than women with a BMI above the median at 11 years of age.

CONCLUSIONS

Two pathways of early growth trigger T2D. Low fat deposition leading to thinness at birth and during infancy results in fat acquisition during childhood. Reduced linear growth leading to short length at birth is associated with lower body fat percentage in adulthood but increased risk of developing diabetes.

Small head circumference at birth and early age at adiposity rebound

AIMS

The adiposity rebound is the age in childhood when body mass index is at a minimum before increasing again. The age at rebound is highly variable. An early age is associated with increased obesity in later childhood and adult life. We have reported that an early rebound is predicted by low weight gain between birth and 1 year of age and resulting low body mass index at 1 year. Here, we examine whether age at adiposity rebound is determined by influences during infancy or is a consequence of foetal growth. Our hypothesis was that measurements of body size at birth are related to age at adiposity rebound.

METHODS

Longitudinal study of 2877 children born in Helsinki, Finland, during 1934-1944.

RESULTS

Early age at adiposity rebound was associated with small head circumference and biparietal diameter at birth, but not with other measurements of body size at birth. The mean age at adiposity rebound rose from 5.8 years in babies with a head circumference of ≤33 cm to 6.2 in babies with a head circumference of >36 cm (P for trend = 0.007). The association between thinness in infancy and early rebound became apparent at 6 months of age. It was not associated with adverse living conditions. In a simultaneous regression, small head circumference at birth, high mother's body mass index and tall maternal stature each had statistically significant trends with early adiposity rebound (P = 0.002, <0.001, 0.004).

CONCLUSION

We hypothesize that the small head size at birth that preceded an early adiposity rebound was the result of inability to sustain a rapid intra-uterine growth trajectory initiated in association with large maternal body size. This was followed by catch-up growth in infancy, and we hypothesize that this depleted the infant's fat stores.