Birth size after embryo cryopreservation: larger by all measures?

STUDY QUESTION: Are the changes in birthweight after frozen and fresh embryo transfer associated with corresponding changes in other measures of foetal growth and placental efficiency? SUMMARY ANSWER: Although placental efficiency was reduced for both frozen and fresh embryo transfer, children born after frozen embryo transfer (frozen-ET) had symmetrically increased size at birth, whereas children born after fresh embryo transfer (fresh-ET) were asymmetrically smaller at birth, compared to naturally conceived children. WHAT IS KNOWN ALREADY: In pregnancies following frozen-ET, the risk of being born large, as measured by birthweight, is higher than after natural and fresh-ET conceptions. It is not known whether this is a result of symmetrically increased growth and increased placental efficiency. STUDY DESIGN, SIZE, DURATION: A Norwegian nationwide registry-based cohort study of 3093 singletons born after frozen-ET, 15 510 singletons born after fresh-ET and 1 125 366 singletons born after natural conception from 1988 to 2015 was performed. We identified 6334 sibships with at least two different conception methods. PARTICIPANTS/MATERIALS, SETTING, METHODS: Data were collected from the Medical Birth Registry of Norway and the Norwegian National Education Database. Main outcome measures were birth length, birthweight, head circumference, ponderal index (birthweight relative to birth length in kg/m3), placental weight, birthweight:placental weight ratio, gestational age, and birthweight z-score. We estimated mean differences between children born after frozen-ET and fresh-ET compared to natural conception, at the population level and within sibships. Adjustments were made for birth year, maternal age, parity, and education. MAIN RESULTS AND THE ROLE OF CHANCE: Estimates at the population level and within sibships were consistent for all outcomes, for both fresh and frozen-ET compared to natural conception. Within sibships, children born after frozen-ET had longer mean length (Δ = 0.42 cm, 95% CI 0.29 to 0.55) and head circumference (Δ = 0.32 cm, 95% CI 0.23 to 0.41) at birth, but a similar ponderal index (Δ = 0.11 kg/m3, 95% CI -0.04 to 0.26), compared to naturally conceived. Children born after fresh-ET had a shorter length (Δ = -0.22 cm, 95% CI -0.29 to -0.15) and head circumference (Δ = -0.15 cm, 95% CI -0.19 to -0.10), and lower ponderal index (Δ = -0.15 kg/m3, 95% CI -0.23 to -0.07) at birth compared to natural conception within sibships. Furthermore, mean placental weight was larger after both frozen-ET (Δ = 37 g, 95% CI 28 to 45) and fresh-ET (Δ = 7 g, 95% CI 2 to 13) compared to natural conception within sibships, whereas mean birthweight:placental weight ratio was reduced for both frozen-ET (Δ = -0.11, 95% CI -0.17 to -0.05) and fresh-ET (Δ = -0.13, 95% CI -0.16 to -0.09). A range of sensitivity analyses all gave similar conclusions as the main models, including restriction to full siblings, restriction to single embryo transfer, and adjustment for maternal BMI, height, and smoking. LIMITATIONS, REASONS FOR CAUTION: Additional adjustment for maternal BMI, height, and smoking was possible only for a small sample of the study population (15%). Data on causes and duration of infertility, as well as treatment details, were limited. WIDER IMPLICATIONS OF THE FINDINGS: The increased birthweight observed in singletons after frozen-ET is associated with a symmetrically increased birth size and large placentas, also after controlling for maternal factors through sibship analyses. Identifying the responsible treatment factors and the long-term health outcomes are particularly important considering the increase in elective freezing of all embryos. STUDY FUNDING/COMPETING INTEREST(S): This work was partly supported by the Central Norway Regional Health Authorities (project number 46045000), the Norwegian University of Science and Technology (project number 81850092) and the Research Council of Norway through its Centres of Excellence funding scheme (project number 262700). The authors have no conflicts of interest to declare. TRIAL REGISTRATION NUMBER: N/A.

Effect of prenatal exposure to organophosphates and pyrethroid pesticides on neonatal anthropometric measures and gestational age.

Several studies have examined the association between prenatal exposure to organophosphate and pyrethroid pesticides and their impact on foetal growth and newborn anthropometry; however, the available evidence is limited and inconclusive. This study examined whether prenatal organophosphate and pyrethroid pesticide exposure was associated with anthropometric measures at birth (weight, length, head circumference), ponderal index, gestational age, and prematurity in 537 mother-child pairs. These were randomly selected from the 800 pairs participating in the prospective birth cohort GENEIDA (Genetics, early life environmental exposures and infant development in Andalusia). Six non-specific organophosphate metabolites (dialkylphosphates, DAPs), one metabolite relatively specific to chlorpyrifos (3,5,6-trichloro-2-pyridinol, TCPy) and a common metabolite to several pyrethroids (3-phenoxybenzoic acid, 3-PBA) were measured in maternal urine from the 1st and 3rd pregnancy trimesters. Information on anthropometric measures at birth, gestational age and prematurity was retrieved from medical records. The sum on a molar basis of DAPs with methyl (Æ©DMs) and ethyl (Æ©DEs) moieties and the sum of the 6 DAPs metabolites (Æ©DAPs) was calculated for both trimesters of pregnancy. High urinary levels of dimethyl phosphate (DMP) during the 3rd trimester were associated with a decrease in birth weight (ß = -0.24; 95% CI: 0.41; -0.06) and birth length (ß = -0.20; 95% CI: 0.41; 0.02). Likewise, ΣDMs during 3rd trimester were near-significantly associated with decreased birth weight (ß = -0.18; 95% CI: 0.37; 0.01). In turn, increased urinary TCPy during 1st trimester was associated with a decreased head circumference (ß = -0.31; 95% CI: 0.57; -0.06). Finally, an increase in 3-PBA in the 1st trimester was associated with a decreased gestational age (ß = -0.36 95% CI: 0.65-0.08), whereas increased 3-PBA at 1st and 3rd trimester was associated with prematurity. These results indicate that prenatal exposure to organophosphate and pyrethroid insecticides could affect normal foetal growth, shorten gestational age and alter anthropometric measures at birth.

Dynamic changes in postnatal growth predict adolescent mental health problems in survivors of extremely low birth weight (ELBW).

Although individuals born at extremely low birth weight (ELBW; ≤1000 g) are known to be at greater risk for mental health problems than individuals born at normal birth weight (NBW; ≥2500 g), contributions of postnatal growth to these relations have not been fully explored. We compared individual differences in the Ponderal Index [(PI; weight(kg)/height(m3)] and head circumference (HC) in predicting internalizing and externalizing behaviors in childhood and adolescence in a cohort of ELBW survivors (N = 137) prospectively followed since birth. Baseline models indicated that infants who were born thinner or with smaller HC showed greater PI or HC growth in the first 3 years. Latent difference score (LDS) models showed that compensatory HC growth in the first year (ΔHC = 20.72 cm), controlled for birth HC, predicted ADHD behaviors in adolescence in those born with smaller HC. LDS models also indicated that the PI increased within the first year (ΔPI = 1.568) but decreased overall between birth and age 3 years (net ΔPI = -4.597). Modeling further showed that larger increases in the PI in the first year and smaller net decreases over 3 years predicted more internalizing behaviors in adolescence. These findings suggest early growth patterns prioritizing weight over height may have negative effects on later mental health in ELBW survivors, consistent with developmental programming theories.

Relationship between the body mass index and the ponderal index with physical fitness in adolescent students.

BACKGROUND: The relationship between the Body Mass Index (BMI) with physical fitness in children and adolescent populations from diverse regions are consistent. However, the relationship between the Ponderal Index (PI) with physical fitness, based on what is known to date, has not been examined in depth. The objective was to evaluate the relationships between BMI and PI with three physical fitness tests of students living at moderate altitudes in Peru. METHODS: A descriptive correlational study was carried out with 385 adolescents, between the ages of 10.0 to 15.9 years old, from the province of Arequipa, Peru. Weight, height, and three physical fitness tests (horizontal jump, agility, and abdominal muscle resistance) were evaluated. BMI and PI were calculated, and they were, then, categorized into three strata (low, normal, and excessive weight). Specific regressions were calculated for sex, using a non-lineal quadratic model for each item adjusted for BMI and PI. RESULTS: The relationship between BMI and PI with the physical tests reflected parabolic curves that varied in both sexes. The regression values for BMI in males oscillated between R2 = 0.029 and 0.073 and for females between R2 = 0.008 and 0.091. For PI, for males, it varied from R2 = 0.044 to 0.82 and for females, from R2 = 0.011 to 0.103. No differences occurred between the three nutritional categories for BMI as well as for PI for both sexes (p range between 0.18 to 0.38), as well as for low weight (BMI vs PI), normal weight (BMI vs PI), and excessive weight (BMI vs PI) (p range between 0.35 to 0.64). CONCLUSIONS: BMI showed inferior quadratic regressions with respect to the PI. In addition, physical performance was slightly unfavorable when it was analyzed by BMI. PI could be a useful tool for analyzing and predicting physical fitness for adolescents living at a moderate altitude since it corrects for the notable differences for weight between adolescents.

Predictors of central and general obesity in Iranian preschool children: which anthropometric indices can be used as screening tools?

AIM: To compare the ability of anthropometric indices [waist-to-hip ratio (WHR), waist-to-height ratio (WHtR), neck-to-height ratio (NHR), conicity index (CI), body adiposity index (BAI), tri-ponderal mass index (TMI) and body mass index (BMI)] and,measuerments like neck(NC), hip(HC) and waist circumferences to predict overweight and obesity in Iranian preschool children. MATERIALS AND METHODS: A total of 498 Iranian preschool children were included in this case-control study conducted in Tehran, Iran. The participants were selected using the stratified random sampling procedure based on gender and school. Using sex-based receiver operating curve (ROC) analysis, we compared the area under the curve and defined the cut-off points for detecting central and general obesity for each index in order to identify the most suitable tools in predicting obesity. RESULTS: Boys had significantly higher values for NC, WC, WHR, NHR, CI, TMI and BMI as compared to girls, whereas BAI and HC were higher in girls. The area under the curve was calculated for all the possible predictors of central obesity, i.e., NC (0.841-0.860), WC (0.70-0.679), HC (0.785-0.697), WHR (0.446-0.639) and CI (0.773-0.653) in boys and girls, respectively. And according to the ROC curve analysis, BMI (0.959-0.948), TMI (0.988-0.981), WHtR (0.667-0.553) and NHR (0.785-0.769) were predictors of general obesity and NC (0.841-0.860) as predictor of central obesity in boys and girls, respectively. The optimal cut-off points for TMI (13.80-15.83), NC (28.68-27.5) and for other anthropometric indices were estimated in both boys and girls. CONCLUSION: TMI and NC seem to predict general and central obesity in Iranian preschool children.

3D Fractional Limb Volume Identifies Reduced Subcutaneous and Lean Mass in Fetal Growth Restriction.

OBJECTIVES: Fetal 2D and 3D fractional limb volume (FLV) measurements by ultrasound can detect fetal lean and subcutaneous mass and possibly percent body fat. Our objectives were to 1) compare FLV measurements in fetuses with fetal growth restriction (FGR) versus small for gestational age (SGA) defined by the International Society of Ultrasound in Obstetrics and Gynecology (ISUOG)-supported international Delphi consensus and 2) correlate FLV findings with birth metrics. We hypothesize that FLV measurements will be significantly smaller in FGR versus SGA fetuses and will correlate closer with Ponderal index (PIx) in the neonate than abdominal circumference (AC). METHODS: Patients were categorized as FGR or SGA as defined by ISUOG. Total thigh volume (TTV), volumes of lean mass (LMV), and fat mass volume (FMV) were calculated from 3D acquisitions. Measurements were compared between groups and correlated with birthweight (BW) and PIx (BW/crown-heal length). RESULTS: The FGR group (n = 37) delivered earlier (37/2 versus 38/0; P = .0847), were lighter (2.2 kg versus 2.6 kg; P = .0003) and had lower PIx (0.023 versus 0.025; P = .0013) than SGAs (n = 22). FGRs had reduced TTV (40.6 versus 48.4 cm3 ; P = .0164), FMV (20.8 versus 25.3 cm3 ; P = .0413), and LMV (19.8 versus 23.1 cm3 ; P = .0387). AC had the highest area under the curve (0.69) for FGR. FMV was more strongly associated with PIx than the AC (P = .0032). CONCLUSIONS: The AC and FLV measurements were significantly reduced in FGR fetuses compared to SGAs. While the AC outperformed FLV in predicting FGR, the FLV correlated best with PIx, which holds investigative promise.

Effects of Ponderal Index on Neonatal Mortality and Morbidities in Extremely Premature Infants.

BACKGROUND: To evaluate how intrauterine stress affects extremely premature infants in terms of intrauterine growth restriction. We hypothesized that extremely premature infants with mildly-low ponderal index (MPI) would have better neonatal outcomes. METHODS: We selected 2,721 subjects of 23 to 28 weeks of gestation between 2013 and 2015 from Korean Neonatal Network database. They were divided into 4 groups based on ponderal index (PI) percentile; PI ≤ 3rd as severely-low PI (SPI, n = 82), 3rd < PI ≤ 10th as MPI (n = 190), 10th < PI ≤ 90th as adequate PI (API, n = 2,179), and PI > 90th as high PI (HPI, n = 270). RESULTS: The mortality in MPI and API groups was comparable (16.3% vs. 16.9%). It was significantly lower than that in the SPI and HPI groups (30.5% and 24.9%, respectively; P = 0.001). The MPI and API groups had better neonatal morbidities compared with the SPI and/or HPI groups, while the MPI group (8.2%) showed a lower incidence of severe intraventricular hemorrhage (IVH) than the other groups (SPI, 21.3%; API, 15.0%; HPI, 19.7%, respectively; P = 0.004). The MPI group had a trend of a bottom in neonatal mortality and morbidities in extremely premature infants. CONCLUSION: The MPI and API groups had lower mortality, massive pulmonary hemorrhage, severe bronchopulmonary dysplasia or death, pulmonary hypertension and neonatal seizure rates than the SPI and/or HPI groups, while the MPI group showed a lower incidence of severe IVH than the other groups. We speculate that the lower incidence of neonatal morbidities and mortality in the MPI group indicating mild intrauterine stress might accelerate fetal maturation resulting in better outcomes in extremely premature infants.

Birth size and morphological femininity in adult women.

BACKGROUND: Women's morphological femininity is perceived to develop under the influence of sex hormones and to serve as a cue of estradiol level, fertility and health in mating context. However, as the studies on direct relationship between femininity and sex steroid levels have reported mixed results, it is still not well understood what factors contribute to inter-women variation in morphological femininity. Epidemiological studies show that indicators of adverse conditions during intrauterine growth and development in utero, such as low birthweight or relative thinness at birth, influence women's physiology ovarian functioning and may be associated with life-time exposure to estradiol in women. Thus, here we tested if birth parameters are also related with the level of morphological femininity in adult women. RESULTS: One hundred sixty-five healthy women of mean age 28.47 years (SD = 2.39) participated in the study. Facial femininity was estimated based on facial width-to-height ratio (fWHR) and facial shape sexual dimorphism measured in the photos. Body femininity was estimated based on waist-to-hip ratio (WHR) and breast size. Birth weight and birth length were obtained from medical records and ponderal index at birth was calculated. No relationship between birth parameters and facial or body femininity in women of reproductive age was found, also when controlled for adult sex steroid levels and BMI. CONCLUSIONS: The results suggest that, although previous research showed that birth parameters predict reproductive development and adult oestradiol level, they do not explain the variance in morphological femininity in women of reproductive age, trait that is thought to be a cue of a woman's estradiol level and fertility in mating context.

Age-Specific Estimates and Comparisons of Youth Tri-Ponderal Mass Index and Body Mass Index in Predicting Adult Obesity-Related Outcomes.

OBJECTIVES: To estimate and compare tri-ponderal mass index (TMI) and body mass index (BMI) at each age from childhood to young adulthood in the prediction of adulthood obesity-related outcomes. STUDY DESIGN: Participants of this observational study (n = 432) were from a 20-year infancy-onset randomized atherosclerosis prevention trial. BMI and TMI were calculated using weight and height measured annually from participants between ages 2 and 20 years. Outcomes were aortic intima-media thickness (at the age of 15, 17, or 19 years), impaired fasting glucose and elevated insulin levels, homeostasis model assessment of insulin resistance index, serum lipids, and hypertension at the age of 20 years. Poisson regressions, Pearson correlation, logistic regression, and area under the curve (AUC) were used to estimate and/or compare associations and predictive utilities between BMI and TMI with all outcomes. RESULTS: The associations and predictive utilities of BMI and TMI with all outcomes were stronger at older ages. BMI had significantly stronger correlations than TMI with insulin (at age 16 years), systolic blood pressure (age 5-20 years), and triglycerides (age 18 years). BMI had significantly greater predictive utilities than TMI for insulin resistance (at age 14-16 years; difference in AUC = 0.018-0.024), elevated insulin levels (age 14-16 years; difference in AUC = 0.018 and 0.025), and hypertension (age 16 to 20 years; difference in AUC = 0.017-0.022) but they were similar for other outcomes. CONCLUSIONS: TMI is not superior to BMI at any ages from childhood to young adulthood in the prediction of obesity-related outcomes in young adulthood.

Organochlorine pesticides residue in placenta and their influence on anthropometric measures of infants.

The objective of this study is to evaluate the influence of placental concentrations of some organochlorine pesticides on newborn's anthropometric measurements (height, weight, head circumference & ponderal index). For this study, we have collected 90 placental tissue samples for the measurement of Dichlorodiphenyltrichloroethane (DDT) & Hexachlocyclohexane (HCH) by Gas Chromatography equipped with Electron Capture Detector (GC-ECD). Regression analysis were performed between outcome variables such as birth weight, birth height, head circumference, ponderal index and independent variable i.e., organochlorine pesticide concentrations. In case of birth weight, there was a substantial decrease of 5.81, 1.94, 4.71, and 2.64 g for 1 ppb (µg/L) increase in placental α-HCH, ß-HCH, γ-HCH, and total HCH concentrations respectively. Significant decrease of 2.02 and 0.43 kg/m3 in ponderal index was found with 1 µg/L increase of total-HCH and total DDT concentrations in placenta. The results of this study support an association between environmental exposure to organochlorine pesticides and anthropometric development of the fetus leading to a significant reduction in its birth weight and ponderal index, slight and non-significant reduction in birth height and head circumference. Efforts should be made to reduce exposure of women of reproductive age in relation to long-term impact on health.

Predictors and reproducibility of urinary organophosphate ester metabolite concentrations during pregnancy and associations with birth outcomes in an urban population.

BACKGROUND: Organophosphate esters (OPEs) are synthetic chemicals used as flame retardants and plasticizers in a variety of goods. Despite ubiquitous human exposures and laboratory evidence that prenatal OPE exposures may disrupt offspring metabolism, perinatal studies of OPE health effects are limited. The objectives of this study were to: 1) Determine predictors and reproducibility of urinary OPE biomarker concentrations during pregnancy, and 2) Estimate the relation of prenatal OPE exposures with birth outcomes and cord blood adipokine and insulin concentrations. METHODS: We analyzed five OPE metabolites in urine samples collected at up to three visits during pregnancy from 90 women enrolled in the ORigins of Child Health And Resilience in Development (ORCHARD) pregnancy cohort in Baltimore, MD from 2017 to 2019. To quantify the variability of metabolite concentrations during pregnancy, we calculated intraclass correlation coefficients (ICCs) for each metabolite using mixed effects regression models. Using self-reported questionnaire data collected during gestation, we assessed possible sociodemographic and environmental/behavioral predictors of each OPE metabolite using generalized estimating equations to account for repeated exposure measures. We ascertained birth outcomes of 76 offspring from medical records, including weight-for-gestational age, length, ponderal index, and gestational age. In a subset of 37 infants, we measured cord blood concentrations of leptin, adiponectin, and insulin. To account for repeated exposure measures, we used linear structural equation models to assess the relations of standard deviation (SD) increases in prenatal OPE metabolite factor scores with continuous birth outcomes and cord blood biomarker concentrations. RESULTS: ICCs ranged from 0.09 for isopropylphenyl-phenyl phosphate (ip-PPP) to 0.59 for bis(1,3-dichloro-2-propyl) phosphate (BDCIPP). We observed little consistency in environmental or behavioral predictors of OPE exposures, although concentrations were generally lower for samples collected in the afternoon compared to morning and winter compared to other seasons. In adjusted analyses, a SD increase in BDCIPP concentration was associated with a 0.06 g/cm3 (95% CI: 0.00, 0.12) greater ponderal index. A SD increase in BDCIPP was associated with a 0.37 (95% CI: - 0.62, - 0.13) SD lower insulin concentration and 0.24 (95% CI: - 0.39, - 0.08) SD lower leptin concentration. Other OPEs were not associated with infant outcomes. CONCLUSIONS: These findings suggest some OPEs may be metabolic disruptors warranting investigation in larger studies.

Fat mass estimation in neonates: anthropometric models compared with air displacement plethysmography.

Newborn adiposity, a nutritional measure of the maternal-fetal intra-uterine environment, is representative of future metabolic health. An anthropometric model using weight, length and flank skinfold to estimate neonatal fat mass has been used in numerous epidemiological studies. Air displacement plethysmography (ADP), a non-invasive technology to measure body composition, is impractical for large epidemiological studies. The study objective was to determine the consistency of the original anthropometric fat mass estimation equation with ADP. Full-term neonates were studied at 12-72 h of life with weight, length, head circumference, flank skinfold thickness and ADP measurements. Statistical analyses evaluated three models to predict neonatal fat mass. Lin's concordance correlation coefficient, mean prediction error and root mean squared error between the predicted and observed ADP fat mass values were used to evaluate the models, where ADP was considered the gold standard. A multi-ethnic cohort of 468 neonates were studied. Models (M) for predicting fat mass were developed using 349 neonates from site 1, then independently evaluated in 119 neonates from site 2. M0 was the original anthropometric model, M1 used the same variables as M0 but with updated parameters and M2 additionally included head circumference. In the independent validation cohort, Lin's concordance correlation estimates demonstrated reasonable accuracy (model 0: 0·843, 1: 0·732, 2: 0·747). Mean prediction error and root mean squared error in the independent validation was much smaller for M0 compared with M1 and M2. The original anthropometric model to estimate neonatal fat mass is reasonable for predicting ADP, thus we advocate its continued use in epidemiological studies.

Relation of Taurine Intake During Pregnancy and Newborns' Growth.

Taurine is a free amino acid and exhibits various biological functions such as brain development, retinal photoreceptor activity, reproduction, normal growth development and antioxidant activity. Taurine is mainly contained in meat and fish foods. Although taurine is inferred to be implicated in the development of the fetus, there are few reports of taurine intake and neonatal growth in pregnant women. Therefore, the purpose of this study was to evaluate the nutrient and taurine intake of pregnant women during the late gestation period using the food intake frequency method. The study was approved by the Institutional Review Board of the Keimyung University. The daily taurine intake of the pregnant women was 104.2 mg. The daily taurine intakes of the pregnant women were divided into three groups for analysis; low, middle, high (<60 mg, 60-120 mg, and >120 mg). The body weight of the top taurine group (3.37 kg) was significantly higher than that of the low and middle groups (3.16 kg, 3.20 kg). Also, the heights of the infants were 49.9 cm, 49.8 cm, and 51.1 cm for each group, showing significantly high measure in the group of taurine intake more than 120 mg/day. There was a positive correlation between the taurine intake of the pregnant women and the height of the newborns. In conclusion, weight and height at birth were significantly higher in the high taurine intake group of the pregnant women. There was a positive correlation between maternal taurine intake and birth length.

Maternal sedentary behavior during pre-pregnancy and early pregnancy and mean offspring birth size: a cohort study.

BACKGROUND: Sedentary behavior is associated with adverse health outcomes in the general population. Whether sedentary behavior during pregnancy is associated with newborn outcomes, such as birth size, is not established, and previous studies have been inconsistent. While previous research suggests that male and female fetuses respond differently to maternal behaviors, such as physical activity, the role of infant sex in sedentary behavior-birth size associations has not been examined. METHODS: Participants in the Omega study, a cohort in Washington State (1996-2008), reported leisure time sedentary behavior (non-work time spent sitting), light intensity physical activity, and moderate/vigorous leisure time physical activity duration in the year before pregnancy (N = 1373) and in early pregnancy (N = 1535, mean 15 weeks). Offspring birth size was abstracted from delivery records. Non-parametric calibration weighting was used to assign adjustment weight (matching the distribution of sociodemographic and medical characteristics of the full cohort (N = 4128)) to participants with available sedentary behavior data. Weighted linear regression models were used to estimate mean differences in offspring birthweight, head circumference, and ponderal index (birthweight/length3) associated with leisure time sedentary behavior. Regression models were run overall and stratified by offspring sex. Isotemporal substitution modeling was used to determine mean differences in birthweight associated with replacing sedentary behavior with light or moderate/vigorous physical activity. RESULTS: On average, women spent 2.3 and 2.6 h/day in leisure time sedentary behavior during pre- and early pregnancy, respectively. There were no associations of pre-pregnancy leisure time sedentary behavior with mean birthweight, head circumference, or ponderal index (adjusted ß = - 12, 95% CI: -28, 4.1; ß = 0.0, 95% CI: -0.04, 0.1; and ß = 0.1, 95% CI: -0.2, 0.4, respectively). Early pregnancy sedentary behavior was not associated with mean birth size. Associations of sedentary behavior with mean birth size did not differ by offspring sex. Replacing sedentary time with light or moderate/vigorous physical activity was not associated with mean birthweight. CONCLUSIONS: We did not observe associations of maternal sedentary behavior during pre- or early pregnancy with mean offspring birth size. Pre-pregnancy and early pregnancy sedentary behavior may have important adverse effects on maternal health, but our results do not support associations with mean offspring birth size.

Maternal vitamin D status, gestational diabetes and infant birth size.

BACKGROUND: Maternal vitamin D status has been associated with both gestational diabetes mellitus (GDM) and fetal growth restriction, however, the evidence is inconsistent. In Finland, maternal vitamin D status has improved considerably due to national health policies. Our objective was to compare maternal 25-hydroxy vitamin D concentrations [25(OH)D] between mothers with and without GDM, and to investigate if an association existed between maternal vitamin D concentration and infant birth size. METHODS: This cross-sectional study included 723 mother-child pairs. Mothers were of Caucasian origin, and infants were born at term with normal birth weight. GDM diagnosis and birth size were obtained from medical records. Maternal 25(OH)D was determined on average at 11 weeks of gestation in pregnancy and in umbilical cord blood (UCB) at birth. RESULTS: GDM was observed in 81 of the 723 women (11%). Of the study population, 97% were vitamin D sufficient [25(OH)D ≥ 50 nmol/L]. There was no difference in pregnancy 25(OH)D concentration between GDM and non-GDM mothers (82 vs 82 nmol/L, P = 0.99). Regression analysis confirmed no association between oral glucose tolerance test results and maternal 25(OH)D (P > 0.53). Regarding the birth size, mothers with optimal pregnancy 25(OH)D (≥ 80 nmol/L) had heavier newborns than those with suboptimal pregnancy 25(OH)D (P = 0.010). However, mothers with optimal UCB 25(OH)D had newborns with smaller head circumference than those with suboptimal 25(OH)D (P = 0.003), which was further confirmed as a linear association (P = 0.024). CONCLUSIONS: Maternal vitamin D concentration was similar in mothers with and without GDM in a mostly vitamin D sufficient population. Associations between maternal vitamin D status and birth size were inconsistent. A sufficient maternal vitamin D status, specified as 25(OH)D above 50 nmol/L, may be a threshold above which the physiological requirements of pregnancy are achieved. TRIAL REGISTRATION: The project protocol is registered in ClinicalTrials.gov in November 8, 2012 ( NCT01723852 ).

Ponderal index at birth associates with later risk of gestational diabetes mellitus.

PURPOSE: Low birth weight (BW) and low ponderal index (PI) are associated with increased risk of type 2 diabetes mellitus. This study has two purposes: first to investigate the influence of PI on the risk of gestational diabetes mellitus (GDM); second, to study the association between glucose metabolism and BW in women with previous GDM. METHODS: GDM cohort: 185 women with GDM in 1978-1996, attending a follow-up study in 2000-2002. Control cohort: 1137 women from a population-based diabetes screening study (Inter99) in a neighbouring county in 1999-2001. BW and birth length were collected from the original midwifery records. BW and PI were stratified into tertiles for analysis. RESULTS: PI in the lower tertiles was associated with an increased risk of GDM [odds ratio 1.59 (95% confidence interval 1.07-2.36, p = 0.021)]. Among women with previous GDM, the area under the curve (AUC) for plasma levels of glucose and insulin during an OGTT was highest for the lower tertiles of BW (for AUCglucose p = 0.048, for AUCinsulin p = 0.047 adjusted for age and BMI). CONCLUSIONS: Lower PI is associated with increased risk of GDM. In women with previous GDM, lower BW is associated with a more severe impairment of glucose metabolism one to two decades after the pregnancy complicated by GDM.

Influence of anthropometric parameters on breastmilk provision in preterm infants.

OBJECTIVE: To explore how growth trends may relate to maternal provision of breastmilk to preterm infants in the Neonatal Intensive Care Unit (NICU). DESIGN: Non-experimental, retrospective, descriptive. SETTING: Level III, 40-bed suburban neonatal intensive care unit (NICU). PARTICIPANTS: 94 preterm infants (<37 post-menstrual age) admitted to the NICU between September 2011 and May 2013. METHODS: This retrospective chart review explored the relationship between infant growth during hospitalization and maternal provision of breastmilk at discharge. Growth data were collected including standard weekly growth measurements from birth through hospital discharge. In addition, average growth over time or growth velocity was assessed for weight (g/kg/d), head circumference (cm/d) and length (cm/d). Growth parameters at birth and discharge were plotted using the Olsen 2010 Growth Calculator for Preterm Infants to obtain standardized assessments of growth percentiles. Key growth factors were examined against the primary investigational outcomes of continued breastmilk provision at discharge and length of hospital stay. Variables included infant characteristics, number of daily direct-to-breast feedings (identified as traditional oral breastfeeding), and maternal characteristics. Statistical tests included student t-test and chi square. Logistic regression models were used to evaluate data and multiple regression was used to examine growth variables. RESULT: In this cohort, 44% of mothers continued to provide breastmilk at the time of infant discharge. Growth velocity was a significant predictor of continued provision of breastmilk at discharge (p=0 0.002, OR 1.39). Ponderal index, combined with other variables were highly predictive of length of stay (p<0.001, R2=0.858). Those infants whose first oral feed was direct-to-breast (versus bottle) were more likely to still be receiving breastmilk at discharge (adj OR 5.3). CONCLUSION: First oral feed being direct-to-breast and higher growth velocity are supportive of continued breastmilk provision throughout hospitalization. These results highlight a need for additional breastfeeding support for mother-infants dyads who provided a bottle as the first oral feed or with poorer growth progression.

Neonatal milk supplementation in lambs has persistent effects on growth and metabolic function that differ by sex and gestational age.

The perinatal environment has a major influence on long-term health and disease risk. Preterm birth alters early-life environment and is associated with altered metabolic function in adulthood. Whether preterm birth per se or the early nutritional interventions used to support growth in preterm infants underpins this association is unknown. Lambs born preterm, following dexamethasone induction of labour, or spontaneously at term were randomised to receive nutrient supplementation, analogous to the milk fortifier used clinically or water as a control for the first 2 weeks after birth. Thereafter, nutrition was not different between groups. Growth was monitored, and the glucose-insulin axis function was assessed in juvenile (4 months) and adult life (14 months). Early nutrition influenced adult metabolic function and body composition to a greater extent than preterm birth. In supplemented females, arginine-stimulated insulin secretion was increased in preterm but reduced in term-born juveniles compared with controls (repeated-measures ANOVA P<0·01). In supplemented preterm males, adult weight, ponderal index (PI) and fasting insulin concentrations were elevated compared with preterm controls (weight, 75 (sem 3) v. 69 (sem 2) kg; PI, 48·0 (sem 2·1) v. 43·7 (sem 1·7) kg/m3; fasting insulin, 0·19 (sem 0·02) v. 0·10 (sem 0·02) ng/ml). Conversely, supplemented term-born males had reduced adult weight, PI and fasting insulin concentrations compared with term-born controls (weight, 64 (sem 2) v. 70 (sem 2) kg; PI, 44·4 (sem 1·8) v. 48·2 (sem 1·7) kg/m3; fasting insulin, 0·09 (sem 0·02) v. 0·14 (sem 0·02) ng/ml; all group×supplement interactions P<0·05). Adult metabolic health may reflect both gestational age at birth and early nutrition. Human studies are urgently needed to investigate the adult sex-specific health implications of neonatal nutritional strategies.

Associations of maternal o,p'-DDT and p,p'-DDE levels with birth outcomes in a Bolivian cohort.

This study examined the potential association of maternal serum levels of o,p'-DDT and p,p'-DDE with gestation time and with anthropometric measurements and thyroid-stimulating hormone (TSH) levels of newborns in a Bolivian birth cohort. Two hundred mothers were consecutively recruited between January and March 2013 at the "Hospital de la Mujer Dr. Percy Boland" in Santa Cruz de la Sierra. Potential confounders were derived from an ad hoc questionnaire. o,p'-DDT and p,p'-DDE were quantified in cord serum by high-resolution gas chromatography coupled with mass spectrometry. Multivariable linear regression analyses were performed, with POP concentrations as independent variables and log-transformed newborn birth outcomes (newborn weight, gestational age, head circumference, birth height, ponderal index, and TSH levels) as dependent variables. o,p'-DDT was detected in 82.5% of samples at median concentration of 0.22ng/mL and p,p'-DDE in 86.5% of samples at median concentration of 1.01ng/mL. Opposite associations with birth weight were found for p,p'-DDE (ß=0.012, p=0.006) and o,p'-DDT (ß=-0.014, p=0.039), and these associations were stronger when both chemicals were entered in the same model. p,p'-DDE was negatively associated with gestation time (ß=-0.004, p=0.012), and o,p'-DDT was borderline negatively associated with newborn head circumference (ß=-0.004, p=0.054). We observed no relevant changes in the magnitude of the coefficients or in statistical significance after adjustment for newborn TSH levels. This study indicates a possible impact of prenatal exposure to o,p'-DDT and p,p'-DDE on newborn anthropometric measurements in a population showing evidence of recent exposure to the pesticide DDT.

Maternal Protein Intake during Pregnancy Is Not Associated with Offspring Birth Weight in a Multiethnic Asian Population.

BACKGROUND: Maternal diet during pregnancy can influence fetal growth. However, the relation between maternal macronutrient intake and birth size outcomes is less clear. OBJECTIVE: We examined the associations between maternal macronutrient intake during pregnancy and infant birth size. METHODS: Pregnant women (n = 835) from the Singapore GUSTO (Growing Up in Singapore Towards healthy Outcomes) mother-offspring cohort were studied. At 26-28 wk of gestation, the macronutrient intake of women was ascertained with the use of 24 h dietary recalls and 3 d food diaries. Weight, length, and ponderal index of their offspring were measured at birth. Associations were assessed by substitution models with the use of multiple linear regressions. RESULTS: Mean ± SD maternal energy intake and percentage energy from protein, fat, and carbohydrates per day were 1903 ± 576 kcal, 15.6% ± 3.9%, 32.7% ± 7.5%, and 51.6% ± 8.7% respectively. With the use of adjusted models, no associations were observed for maternal macronutrient intake and birth weight. In male offspring, higher carbohydrate or fat intake with lower protein intake was associated with longer birth length (ß = 0.08 cm per percentage increment in carbohydrate; 95% CI: 0.04, 0.13; ß = 0.08 cm per percentage increment in fat; 95% CI: 0.02, 0.13) and lower ponderal index (ß = -0.12 kg/m(3) per percentage increment in carbohydrate; 95% CI: -0.19, -0.05; ß = -0.08 kg/m(3) per percentage increment in fat; 95% CI: -0.16, -0.003), but this was not observed in female offspring (P-interaction < 0.01). CONCLUSIONS: Maternal macronutrient intake during pregnancy was not associated with infant birth weight. Lower maternal protein intake was significantly associated with longer birth length and lower ponderal index in male but not female offspring. However, this finding warrants further confirmation in independent studies. This trial was registered at clinicaltrials.gov as NCT01174875.