Neonatal Body Size Research Articles

Reproductive toxicity and molecular responses induced by telmisartan in Daphnia magna at environmentally relevant concentrations

With aging population increasing globally, the use of pharmaceutically active compounds is rising. The cardiovascular drug telmisartan has been widely detected in various environmental compartments, including biota, surface waters, and sewage treatment plant effluents at concentrations ranging from ng/L to μg/L levels. This study evaluated the effects of telmisartan on the microcrustacean Daphnia magna at a wide range of concentrations (0.35, 0.70, 1.40, 500, and 1000 μg/L) and revealed significant ecotoxicological implications of this drug, even at environmentally relevant concentration. Acute exposure to telmisartan (1.40, 500, and 1000 μg/L) resulted in a notable decrease in heart rate, while chronic exposure accelerated the time to the first brood by 3 days and reduced neonate body size. Molecular investigations revealed marked downregulation of vitellogenin genes (Vtg1 and Vtg2). Non-monotonic dose responses were observed for gene expression, early-stage body length, and the total number of offspring produced, while the heart rate and time to the first brood showed clear concentration-dependent responses. These findings highlight the potential risks, notably to reproductive capacity, associated with exposure to telmisartan in environmentally relevant concentration, suggesting the need for further studies on the potential long-term ecological consequences.

Association of maternal insulin resistance with neonatal insulin resistance and body composition/size: a prospective cohort study in a sub-Saharan African population.

We prospectively evaluated the association of the insulin resistance of third-trimester Nigerian pregnant women with their newborn infants' insulin resistance and birth size. Pregnancy-associated insulin resistance (IR), often assessed with homeostatic model assessment of IR (HOMA-IR), is associated, especially among women with gestational diabetes (GDM), with abnormal neonatal birth size and body composition, predisposing the baby to metabolic disorders like diabetes and obesity. The associations of maternal IR with neonatal IR, birth size and body composition are less studied in nondiabetic pregnant women, especially in sub-Saharan settings like Nigeria. We originally recruited 401 third trimester, nondiabetic pregnant women to a prospective cohort study, followed up until birth. Blood samples of mothers and babies were obtained, respectively, at recruitment and within 24 hours postbirth for fasting serum glucose (FSG) and insulin (FSI) assays, and HOMA-IR was calculated as [(FSI × FSG)/22.5)]. Complete data for 150 mother-baby dyads was analysed: the mothers, with a mean (standard deviation [SD]) age of 31.6 (4.5) years, had live births at a mean (SD) gestational age of 39.2 weeks. The proportions of infants with wasting, stunting, impaired fetal growth (either wasting or stunted), small-for-gestation-age, large-for-gestational-age, low birthweight, and macrosomia were 4.2% (95% confidence interval, 1.1-10.3), 19.7% (12.9-28.0), 23.1% (15.8-31.8), 10.1% (5.3-17.0), 12.6% (7.2-19.9), 0.8% (0.02-4.5), and 5.0% (1.8-10.5), respectively. Maternal HOMA-IR was not associated with neonatal HOMA-IR (p=0.837), birth weight (p=0.416) or body composition measured with weight-length ratio (p=0.524), but birth weight was independently predicted by maternal weight (p=0.006), body mass index (p=0.001), and parity (p=0.012). In this nondiabetic/non-GDM cohort, maternal HOMA-IR was not associated with neonatal IR, body size or body composition. Larger studies are required to confirm these findings, with addi-tional inclusion of mothers with hyperglycaemia for comparison.

Neonatal adiposity is associated with microRNAs in adipocyte-derived extracellular vesicles in maternal and cord blood, a discovery analysis.

Maternal body size, nutrition, and hyperglycemia contribute to neonatal body size and composition. There is little information on maternal-fetal transmission of messages which influence fetal growth. We analyzed adipocyte-derived small extracellular vesicular (ADsEV) microRNAs in maternal and cord blood to explore their adipogenic potential. There were 279 mother-neonate pairs with all phenotypic data (normal glucose tolerant NGT = 148, gestational diabetes mellitus GDM = 131). Neonates with adiposity were those in the highest tertile (T3) of sex-specific sum of skinfolds and those without adiposity (lean) in the lowest tertile T1 of NGT pregnancies. We studied ADsEV miRNAs in 76 and 51 neonates with and without adiposity respectively and their mothers based on power calculations (68 NGT and 59 GDM pregnancies). ADsEV miRNAs from maternal and cord blood plasma samples were profiled on Agilent 8*60 K microarray. Differential expression (DE) of ADsEV miRNAs in adipose vs. lean groups was studied before and after adjustment for maternal GDM, adiposity, and vitamin B12-folate status. Multiple miRNAs were common in maternal and cord blood and positively correlated. We identified 24 maternal and 5 cord blood miRNAs differentially expressed (discovery p ≤ 0.1) in the adipose group in unadjusted, and 19 and 26, respectively, in the adjusted analyses. Even though DE miRNAs were different in maternal and cord blood, they targeted similar adipogenic pathways (e.g., the forkhead box O (FOXO) family of transcription factors, mitogen‑activated protein kinase (MAPK) pathway, transforming growth factor beta (TGF-β) pathway). Maternal GDM and adiposity were associated with many DE ADsEV miRNAs. Our results suggest that the ADsEV miRNAs in mothers are potential regulators of fetal adiposity. The expression and functionality of miRNAs appear to be influenced by maternal adiposity, hyperglycemia, and micronutrient status during pregnancy.

Association of Pre-Pregnancy BMI and Gestational Weight Gain with Neonatal Body Size: A Cross- Sectional Study

Association of Pre-Pregnancy BMI and Gestational Weight Gain with Neonatal Body Size: A Cross- Sectional Study

I got it from my mother: Inter-nest variation of mercury concentration in neonate Smooth-fronted Caiman (Paleosuchus trigonatus) suggests maternal transfer and possible phenotypical effects

The deleterious effects of mercury (Hg) contamination are well documented in humans and wildlife. Chronic exposure via diet and maternal transfer are two pathways which increase the toxicological risk for wild populations. However, few studies examined the physiological impact of Hg in crocodilians. We investigated the Hg contamination in neonate Smooth-fronted Caimans, Paleosuchus trigonatus, and the use of keratinized tissues and blood to evaluate maternal transfer. Between November 2017 and February 2020, we sampled 38 neonates from 4 distinct nests. Mercury concentration was measured in claws, scutes and total blood. Highest Hg concentrations were found in claws. Strong inter-nest variations (Hg ranging from 0.17 ± 0.02 to 0.66 ± 0.07 μg.g−1 dw) presumably reflect maternal transfer. Reduced body size in neonates characterized by elevated Hg concentrations suggests an influence of Hg during embryonic development. We emphasize the use of claws as an alternative to egg collection to investigate maternal transfer in crocodilians. Our results demonstrated the need of further investigation of the impact of Hg contamination in the first life stages of crocodilians.

Abstract 16738: Association Between First and Second Trimester Maternal Screening Biochemistry, Ultrasound, and Fetal Brain Growth in Presence of Fetal or Maternal Congenital Heart Disease

Introduction: Newer research has highlighted significant neurological impairments in children and adults with congenital heart disease (CHD). The more severe the heart defect, the higher the neurologic impairment. Pregnancies complicated by fetal or maternal CHD carry a higher risk of placental abnormalities. We studied the association between pregnancy hormonal levels and fetal head and body growth. Hypothesis: Placental dysfunction in pregnancies with fetal or maternal CHD alters pregnancy hormonal levels affecting fetal brain and somatic growth. Methods: We performed a retrospective case-control study on pregnant women (year 2010-2019) at the University of Iowa. Only women with first and/or second trimester prenatal screening (ultrasound and blood test) were included. Pregnancies with fetal chromosomal abnormalities, multiple gestation, maternal diabetes, smoking, or hypertension were excluded. Pregnancies were either healthy controls (n=36), women with CHD (MCHD; n=26), or fetus with CHD (FCHD; n=23). Pregnancy hormonal levels, ultrasound findings, and fetal/neonatal growth percentiles and/or z-scores data were analyzed. Results: Women with CHD were younger (p=0.004) with increased fetal nuchal translucency (p=0.003) compared to controls. Women in MCHD (p=0.02) and FCHD (p=0.02) group delivered earlier than controls. FCHD had significantly lower pregnancy associated plasma protein-A (PAPP-A) levels than controls (p=0.04). The groups had no difference in the second trimester fetal head circumference (HC) and femur length. FCHD group had significantly smaller HC percentile (p=0.03) and z-scores (p=0.03) at birth than controls. Both FCHD and MCHD had smaller birth weight and length compared to controls. However, only FCHD group demonstrated significantly lower HC to birth weight ratio (p=0.01). The controls had a positive correlation between human chorionic gonadotropin level and head circumference z-score at birth (r=0.34;p=0.053). Conclusions: Pregnant women with CHD have increased fetal nuchal translucency and deliver at earlier gestational age. Women with fetal CHD have smaller neonatal head and body size at birth with associated low PAPP-A level early in their pregnancy probably related to placental dysfunction.

Does cord blood leptin level mediate the association between neonatal body size and postnatal growth? Results from the EDEN mother–child cohort study

Background: Leptin is potentially involved in the correction of early postnatal growth of infants having deviated from their genetic trajectory in utero.Aim: To analyse the potential mediating role of cord blood leptin level in the association between neonatal anthropometry and early postnatal growth in the mother–child EDEN cohort.Subjects and methods: We included term newborns with information on leptin, birth weight and length, and weight and length SD-score changes over the first 2 months. The Baron and Kenny method was used to quantify the mediation contribution of leptin in the association between neonatal anthropometry and postnatal growth, considering several confounders. Analyses were stratified to consider sexual dimorphism.Results: A 1 SD higher birth weight was associated with a lower 2-months weight variation of 0.27 (0.18; 0.36) SD and a 0.16 (0.06; 0.26) SD, in boys and girls, respectively. Leptin explained 20% and 25% of these associations, respectively. Leptin did not mediate the association between birth length and birth-to-2 months length variation.Conclusion: Our results suggest that cord blood leptin may not be involved in the negative association between birth length and postnatal length growth but may play a modest mediating role in early postnatal catch-up or catch-down in weight.

Heterozygosity-Fitness Correlations Reveal Inbreeding Depression in Neonatal Body Size in a Critically Endangered Rock Iguana.

Inbreeding depression, though challenging to identify in nature, may play an important role in regulating the dynamics of small and isolated populations. Conversely, greater expression of genetic load can enhance opportunities for natural selection. Conditional expression concentrates these opportunities for selection and may lead to failure of detection. This study investigates the possibility for age-dependent expression of inbreeding depression in a critically endangered population of rock iguanas, Cyclura nubila caymanensis. We employ heterozygote-fitness correlations to examine the contributions of individual genetic factors to body size, a fitness-related trait. Nonsignificant reductions in homozygosity (up to 7%) were detected between neonates and individuals surviving past their first year, which may reflect natural absorption of inbreeding effects by this small, fecund population. The majority of variation in neonate body size was attributed to maternal or environmental effects (i.e., clutch identity and incubation length); however, heterozygosity across 22 microsatellite loci also contributed significantly and positively to model predictions. Conversely, effects of heterozygosity on fitness were not detectable when adults were examined, suggesting that inbreeding depression in body size may be age dependent in this taxon. Overall, these findings emphasize the importance of taking holistic, cross-generational approaches to genetic monitoring of endangered populations.

Temporal regulation of Lin28a during mammalian neurulation contributes to neonatal body size control.

The timing of developmental events is tightly regulated along a time axis for normal development. Although the RNA-binding protein Lin28a plays a crucial role in the regulation of developmental timing in Caenorhabditis elegans, how the timing of Lin28a expression affects the rate and/or duration of developmental events during mammalian development remains to be addressed. In this study, we discovered that the timing and the duration of Lin28a expression affect embryonic growth. During the neurulation stage of mouse development, endogenous Lin28a levels start to drop. When Lin28a expression was maintained transiently using the inducible tetracycline-regulated gene expression (Tet-ON) system [doxycycline (Dox)-inducible Lin28a transgenic (iLin28a Tg) mice] with Dox administration at E8.5 and E9.5, it resulted in neonatal lethality, increased body weight (organomegaly), and an increased number of caudal vertebrae at birth. On the other hand, Lin28a induction only at E8.5 caused neonatal lethality and organomegaly, but did not affect the caudal vertebra number. Of note, although Dox treatment before or after neurulation still caused neonatal lethality, it neither caused organomegaly nor the increased caudal vertebra number in iLin28a Tg neonates. Temporal regulation of Lin28a expression during neurulation affects developmental events such as cessation of axial elongation and embryonic growth in mice.

Impacts of maternal characteristics and temperature on juvenile survival in the crocodile lizard: Implications for conservation.

Captive breeding is an important conservation measure that may restore and enhance wild populations of rare and endangered species. Multiple anthropogenic hazards have brought the crocodile lizard, Shinisaurus crocodilurus, to the brink of extinction. We initiated a captive breeding program and quantified female reproductive traits, including reproductive timing, litter size, litter mass, and neonate size. To identify the internal and external factors affecting female reproductive function, we then analyzed how maternal age is related to body size, temperature, and female reproductive traits. We found that larger female crocodile lizards produced more offspring than smaller ones, as both litter size and litter mass were positively related to maternal body size. In contrast, neonate size was independent of maternal body size. Maternal reproductive output varied among different age groups. Young and old females had significantly smaller living litter size and mass than middle-aged females. Among captive females, one-third exhibited early parturition in autumn and winter instead of the following spring, a pattern probably associated with higher ambient temperatures in captivity. Although female reproductive output and neonatal body size did not differ between early- and normal-parturition females, offspring from the former group died earlier than those from the latter. Our study highlights the danger of climate change in hastening parturition, a phenomenon that could significantly hamper neonate survival and impede population recruitment.

Effect of food quality on life history traits of <i>Daphnia galeata</i> and <i>Bosmina fatalis</i>

枝角类体内氮磷比与生活史策略的选择密切相关，大型枝角类通常体内含磷量高、个体生长快、生殖率高，而小型枝角类体内含磷量低，个体生长相对较慢、生殖率低.由于大型枝角类对磷的需求比较高，我们假设大型枝角类生活史各参数对食物磷缺乏比小型枝角类更为敏感.本研究比较分析了食物碳磷比对流溪河水库两种枝角类（盔型溞（Daphnia galeata）和脆弱象鼻溞（Bosmina fatalis））生活史各参数的影响.实验设计了3个食物质量处理组：高磷（碳：磷=105）、中磷（400）和低磷（1450），食物浓度均为2 mg C/L的蛋白核小球藻（Chlorella pyrenoidosa）.脆弱象鼻溞内禀增长率、幼溞生长速率、平均每窝产仔量和首次生殖时体长均随着食物碳磷比的升高而显著下降；首次生殖时间则随着食物碳磷比的升高而显著延长；新生幼溞体长在各食物处理中无显著差异.盔型溞幼溞生长速率、平均每窝产仔量和首次生殖时体长均随着食物碳磷比的升高而显著下降；内禀增长率和新生幼溞体长在高磷处理组显著高于中磷和低磷处理组，但在中磷和低磷处理组无显著差异；首次生殖时间在高磷处理组显著短于中磷和低磷处理组，但在中磷和低磷处理组无显著差异.结果表明，食物的磷缺乏降低了两种枝角类的内禀增长率和幼溞生长速率，并延长了性成熟时间；盔型溞的内禀增长率、首次生殖时间和平均每窝产仔量等生活史参数受食物磷限制的程度小于脆弱象鼻溞，导致盔型溞对脆弱象鼻溞有竞争优势.;Primary life history parameters of cladocerans are linked to body N:P stoichiometry. Large cladocerans tend to have higher phosphorus content, grow more rapidly, and produce more neonates than small cladocerans. The entire difference in specific phosphorus content of these two cladoceran groups can be related to differences in RNA content. Large cladocerans' high growth rate requires a high ribosomal complement for extensive protein synthesis coupled to high growth rate. Therefore, large cladocerans' life history straits are supposed to be more sensitive to food phosphorus deficiency than those of small cladocerans. We examined the effects of food stoichiometry quality (different carbon:phosphorus[C:P] ratios)on life history straits of two common cladocerans species in South China, Daphnia galeata and Bosmina fatalis. D. galeata and B. fatalis were fed saturating concentrations of food (Chlorella pyrenoidosa, 2 mg C/L)of high P (C:P=105), medium P (400), and low P (1450). Population intrinsic growth rates varied from 0.36 to 0.46 d^-1 and 0.18 to 0.39 d^-1, neonate body growth rates varied from 0.31 to 0.52 d^-1 and 0.10 to 0.38 d^-1, age at first reproduction varied from 4.6 to 7.2 d and 3.4 to 7.2 d, mean clutch size varied from 11.5 to 15.1 ind. and 1.6 to 2.3 ind., and newborn neonate body size varied from 0.65 to 0.71 mm and 0.22 to 0.23 mm for D. galeata and B. fatalis, respectively. Neonate body growth rate, population intrinsic growth rate, body size at first reproduction and mean clutch size tend to decrease, while age at first reproduction tend to increase with the increasing of food C:P ratio in both species. Newborn neonate body size was much higher under high P condition than those under medium and low P conditions in D. galeata, but showed no significant difference among treatments in B. fatalis. Our results suggest that population intrinsic growth rate, neonate growth rate and age at first reproduction of D. galeata tend to be less sensitive to food phosphorus deficiency than those of B. fatalis, and D. galeata is competitively superior to B. fatalis.

Influence of aerobic exercise on maternal lipid levels and offspring morphometrics

Maternal BMI, lipid levels (cholesterol, triglyceride, LDL, HDL), and exercise amount are interrelated and each influence offspring body size. This study proposed to determine the influence of exercise on maternal lipid levels and infant body size. We had 36 participants complete these measures. Participants in the aerobic exercise intervention (n = 14) completed three 50-min sessions weekly from 16 weeks gestation to delivery and were compared with a non-exercise control group (n = 22). Maternal lipid profiles were assessed at 16 and at 36 weeks gestation. Fetal body size was measured at 36 weeks gestational age using ultrasound assessment. Neonatal body size measures were acquired from birth records. Statistical analysis included two-sample t-tests, correlations, and regression models. Participants were similar in age, pre-pregnancy BMI, gravida, parity, education, and gestational weight gain (GWG). There were no differences in gestational age, Apgar scores at 1 and 5 min for infants of exercisers relative to controls. Exercisers had higher pre-training triglycerides (p = 0.004) and pregnancy change in triglycerides (p = 0.049) compared to controls. Head circumference was significantly larger in exercise exposed infants relative to infants of controls. Pregnancy METs had a positive relationship with birth length (r = .445, p = .006) and birth weight (r = .391, p = .02). GWG had a moderate, positive relationship with fetal abdominal circumference (r = .570, p = .004). Regression analysis indicated 5 predictors explained 61.7% of the variance in birth weight (Adj.R2 = 0.469, F(5,13) = 5,13, p = 0.02); it was found that pregnancy METs (β = .724, p = .007), 36 week cholesterol (β = 1.066, p = .02), and 36 week LDL (β = -1.267, p = .006) significantly predict birth weight. Regression analysis indicated 4 predictors explained 43.8% of the variance in birth length (Adj.R2 = 0.306, F(4,17) = 3.32, p = 0.04); it was found that pregnancy METs (β = .530, p = .03), and 36 week LDL (β = -.891, p = .049) significantly predict birth length. The primary association and predictors of infant body size was related to pregnancy exercise and late pregnancy cholesterol and LDL levels. Considering these relationships, it is essential that women maintain aerobic exercise during pregnancy, but should also be cognizant of lipid levels during their pregnancy. Therefore intervention during pregnancy focused on infant body size should involve exercise and and quality nutritional intake foods during pregnancy.

Dosing antibiotics in neonates: review of the pharmacokinetic data.

Antibiotics are often used in neonates despite the absence of relevant dosing information in drug labels. For neonatal dosing, clinicians must extrapolate data from studies for adults and older children, who have strikingly different physiologies. As a result, dosing extrapolation can lead to increased toxicity or efficacy failures in neonates. Driven by these differences and recent legislation mandating the study of drugs in children and neonates, an increasing number of pharmacokinetic studies of antibiotics are being performed in neonates. These studies have led to new dosing recommendations with particular consideration for neonate body size and maturation. Herein, we highlight the available pharmacokinetic data for commonly used systemic antibiotics in neonates.

Prenatal Vitamin D Intake, Cord Blood 25-Hydroxyvitamin D, and Offspring Body Composition: The Healthy Start Study.

Vitamin D deficiency in pregnancy may be associated with increased offspring adiposity, but evidence from human studies is inconclusive. We examined associations between prenatal vitamin D intake, 25-hydroxyvitamin D (25(OH)D) in cord blood, and offspring size and body composition at birth and 5 months. Participants included 605 mother-offspring dyads from the Healthy Start study, an ongoing, pre-birth prospective cohort study in Denver, Colorado, USA. Prenatal vitamin D intake was assessed with diet recalls and questionnaires, and offspring body composition was measured via air displacement plethysmography at birth and 5 months. General linear univariate models were used for analysis, adjusting for maternal age, race/ethnicity, pre-pregnancy body mass index (BMI), offspring sex, and gestational age at birth. Non-Hispanic white race, lower pre-pregnancy BMI, higher prenatal vitamin D intake, and summer births were associated with higher cord blood 25(OH)D. Higher 25(OH)D was associated with lower birthweight (β = –6.22, p = 0.02), but as maternal BMI increased, this association became increasingly positive in direction and magnitude (β = 1.05, p = 0.04). Higher 25(OH)D was also associated with lower neonatal adiposity (β = –0.02, p < 0.05) but not after adjustment for maternal BMI (β = –0.01, p = 0.25). Cord blood 25(OH)D was not associated with offspring size or body composition at 5 months. Our data confirm the hypothesis that vitamin D exposure in early life is associated with neonatal body size and composition. Future research is needed to understand the implications of these associations as infants grow.

Maternal plasma phosphatidylcholine polyunsaturated fatty acids during pregnancy and offspring growth and adiposity

BackgroundPolyunsaturated fatty acids (PUFA) are essential for offspring development, but it is less clear whether pregnancy PUFA status affects growth and adiposity. MethodsIn 985 mother-offspring pairs from the ongoing Singaporean GUSTO cohort, we analyzed the associations between offspring growth and adiposity outcomes until age 5 years and five PUFAs of interest, measured in maternal plasma at 26–28 weeks’ gestation: linoleic acid (LA), arachidonic acid, α-linolenic acid, eicosapentaenoic acid, and docosahexaenoic acid (DHA). We measured fetal growth by ultrasound (n=924), neonatal body composition (air displacement plethysmography (n=252 at birth, and n=317 at age 10 days), and abdominal magnetic resonance imaging (n=317)), postnatal growth (n=979) and skinfold thicknesses (n=981). Results were presented as regression coefficients for a 5% increase in PUFA levels. ResultsLA levels were positively associated with birthweight (β (95% CI): 0.04 (0.01, 0.08) kg), body mass index (0.13 (0.02, 0.25) kg/m2), head circumference (0.11 (0.03, 0.19) cm), and neonatal abdominal adipose tissue volume (4.6 (1.3, 7.8) mL for superficial subcutanous tissue, and 1.2 (0.1, 2.4) mL for internal tissue), but not with later outcomes. DHA levels, although not associated with birth outcomes, were related to higher postnatal length/height: 0.63 (0.09, 1.16) cm at 12 months and 1.29 (0.34, 2.24) cm at 5 years. ConclusionsLA was positively associated with neonatal body size, and DHA with child height. Maternal PUFA status during pregnancy may influence fetal and child growth and adiposity.

The Association of Cord Blood 25(OH)D Levels with Neonatal Body Size and Composition: The Healthy Start Study

Micronutrient deficiencies during pregnancy are associated with an increased risk of chronic disease in offspring. There is some evidence that vitamin D deficiency in pregnancy is associated with increased offspring adiposity, but evidence from human studies is inconclusive. We examined associations of vitamin D (25‐hydroxyvitamin D [25(OH)D]) in cord blood with neonatal size and body composition in 600 mother‐infant dyads from the Healthy Start study, an ongoing, pre‐birth prospective cohort study in Denver, Colorado. Total 25(OH)D (nmol/L) was measured in cord blood serum collected at delivery (39.6±1.1 weeks gestation). Weight‐for‐gestational‐age z‐scores (WGAZ) were calculated from birth weight (g) and birth length (cm) measured at delivery. Neonatal fat mass (g) and fat‐free mass (g) were measured (median 1 day post‐birth) via air displacement plethysmography (PEA POD). We used multivariable linear regression to examine the association of cord blood 25(OH)D with neonatal outcomes, adjusting for maternal age, education, income, race/ethnicity, pre‐pregnant BMI, prenatal smoking, prenatal physical activity, gestational diabetes, gestational weight gain, offspring gestational age at birth, season of birth, and infant sex. We also evaluated effect modification by maternal race/ethnicity and pre‐pregnant BMI. We observed interactions of total 25(OH)D with race/ethnicity for the outcome of offspring birth weight and with maternal pre‐pregnant BMI for the outcomes of offspring birth weight and fat mass (p&lt;0.05 for all interaction terms). The association between birth weight and 25(OH)D was modified by race (p=0.04). The largest effect was observed in Hispanic participants (β= −103.8 grams per 1 nmol/L increase in 25(OH)D, p=0.003) with smaller effects observed among non‐Hispanic white (β= −55.8g, p=0.03), non‐Hispanic black (β= −44.4g, p=0.21), and other (β= −44.4g, p= 0.28) offspring. Associations of total 25(OH)D with birth weight (p=0.02) and fat mass (p=0.04) also differed by maternal pre‐pregnant BMI. Each kg/m2 increase in pre‐pregnant BMI increased the magnitude of the association between 25(OH)D and birth weight by 0.24g per nmol/L 25(OH)D (p=0.02) and between 25(OH)D and fat mass by 0.08g per nmol/L 25(OH)D (p=0.04). Total 25(OH)D was not associated with offspring birth length (p=0.59), fat‐free mass (p=0.61), or WGAZ (p=0.79). In conclusion, we found that total cord blood 25(OH)D is associated with neonatal size and body composition, although the strength and direction of these associations differ according to maternal race/ethnicity and pre‐pregnant BMI. Further research is needed to understand the implications of these associations as infants grow.Support or Funding InformationSupported by the National Institutes of Health and the American Heart Association

Effect of supervised exercise training during pregnancy on neonatal and maternal outcomes among overweight and obese women. Secondary analyses of the ETIP trial: A randomised controlled trial

BackgroundMaternal obesity associates with complications during pregnancy and childbirth. Our aim was to investigate if exercise during pregnancy in overweight/obese women could influence birth weight or other neonatal and maternal outcomes at delivery.Material and methodsThis is a secondary analysis of a randomised controlled trial of exercise training in pregnancy for women with body mass index (BMI) ≥ 28 kg/m2. Ninety-one women (31.3 ± 4.3 years, BMI 34.5 ± 4.2 kg/m2) were allocated 1:1 to supervised exercise during pregnancy or to standard care. The exercise group was offered three weekly training sessions consisting of 35 minutes of moderate intensity walking/running followed by 25 minutes of strength training. Data from 74 women (exercise 38, control 36) were analysed at delivery.ResultsBirth weight was 3719 ± 695 g in the exercise group and 3912 ± 413 g in the control group (CI -460.96, 74.89, p = 0.16). Birth weight > 4000 g was 35% in the exercise group and 52% in the control group (p = 0.16). Mean gestational age at delivery was 39.1 weeks in the exercise group and 39.5 weeks in the control group (CI -1.33, 0.43, p = 0.31). No significant between-group differences were found in neonatal body size, skinfold thickness, placental weight ratio, or Apgar score. The prevalence of caesarean section was 24% in the exercise group and 17% in the control group (CI 0.20, 2.05, p = 0.57). Mean length of hospital stay was 4.8 days in the exercise group and 4.5 days in the control group (CI -0.45, 1.00, p = 0.45).ConclusionsOffering supervised exercise during pregnancy for overweight and obese women did not influence birth weight or other neonatal and maternal outcomes at delivery. However our trial was limited by low sample size and poor adherence to the exercise protocol, and further research is needed.Trial registrationClinicalTrials.gov NCT01243554

Blood pressure during pregnancy, neonatal size and altered body composition: the Healthy Start study.

ObjectiveTo estimate associations between changes in maternal arterial pressure during normotensive pregnancies and offspring birthweight and body composition at birth.Study DesignProspective study of 762 pregnant normotensive Colorado women, recruited from outpatient obstetrics clinics. Repeated arterial pressure measurements during pregnancy were averaged within the second and third trimesters, respectively. Multivariable regression models estimated associations between second to third trimester changes in arterial pressure and small-for-gestational-age birthweight, fat mass, fat-free mass, and percent body fat.ResultsA greater second to third trimester increase in maternal arterial pressure was associated with greater odds of small-for-gestational-age birthweight. Greater increases in maternal diastolic blood pressure were associated with reductions in offspring percent body fat (−1.1% in highest versus lowest quartile of increase, 95% confidence interval: −1.9%, −0.3%).ConclusionsMid-to-late pregnancy increases in maternal arterial pressure which do not meet clinical thresholds for hypertension are associated with neonatal body size and composition.

0266 Relationships of neonatal beef calf birth weight and body size measures

0266 Relationships of neonatal beef calf birth weight and body size measures

Maternal dietary intake during pregnancy and offspring body composition: The Healthy Start Study

Consistent evidence of an influence of maternal dietary intake during pregnancy on infant body size and composition in human populations is lacking, despite robust evidence in animal models. We sought to evaluate the influence of maternal macronutrient intake and balance during pregnancy on neonatal body size and composition, including fat mass and fat-free mass. The analysis was conducted among 1040 mother-offspring pairs enrolled in the prospective prebirth observational cohort: the Healthy Start Study. Diet during pregnancy was collected using repeated 24-hour dietary recalls (up to 8). Direct measures of body composition were obtained using air displacement plethysmography. The National Cancer Institute measurement error model was used to estimate usual dietary intake during pregnancy. Multivariable partition (nonisocaloric) and nutrient density (isocaloric) linear regression models were used to test the associations between maternal dietary intake and neonatal body composition. The median macronutrient composition during pregnancy was 32.2% from fat, 15.0% from protein, and 47.8% from carbohydrates. In the partition multivariate regression model, individual macronutrient intake values were not associated with birthweight or fat-free mass, but were associated with fat mass. Respectively, 418 kJ increases in total fat, saturated fat, unsaturated fat, and total carbohydrates were associated with 4.2-g (P= .03), 11.1-g (P= .003), 5.9-g (P= .04), and 2.9-g (P=.02) increases in neonatal fat mass, independent of prepregnancy body mass index. In the nutrient density multivariate regression model, macronutrient balance was not associated with fat mass, fat-free mass, or birthweight after adjustment for prepregnancy body mass index. Neonatal adiposity, but not birthweight, is independently associated with increased maternal intake of total fat, saturated fat, unsaturated fat, and total carbohydrates, but not protein, suggesting that most forms of increased caloric intake contribute to fetal fat accretion.