Fetal Growth Indices Research Articles

Periconceptional Seafood Intake and Fetal Growth.

Previous reports of associations of maternal seafood intake with fetal growth were inconsistent. Further, little is known whether associations differ across seafood subtypes or fetal growth indices. Among 3141 participants of the Omega study, a pregnancy cohort study, we investigated associations of periconceptional shell, lean, and fatty fish intake with fetal growth indices. We categorised food frequency questionnaire reported seafood intake into frequencies of: <0.2 servings/month, 0.2 servings/month -<0.5 servings/week, 0.5-1 servings/week, and >1 servings/week. We abstracted birthweight, birth length, and head circumference from medical records. Using generalised linear models with a log link, the Poisson family, and robust standard errors, we estimated relative risks and 95% confidence intervals (CI) for low birthweight (LBW, <2500 g) and linear regression models to estimate mean differences for continuous fetal growth indices across seafood intake categories. Medians (interquartile range) of shell, lean, and fatty fish intake were 0.3 (0-0.9), 0.5 (0-1.0), and 0.5 (0.1-1.0) servings/week, respectively. Lean fish intake of >1 servings/week (vs. <0.2 servings/month) was associated with a 2.2-fold higher risk of LBW (95% CI 1.2, 4.1). Shellfish intake of >1 servings/week (vs. <0.2 servings/month) was associated with a 0.6 kg/m(3) higher mean ponderal index (95% CI 0.0, 1.2 kg/m(3) ). There was no evidence for associations of total seafood or seafood subtype intake with other fetal growth indices. Higher intakes of lean fish and shellfish were associated with a higher risk of LBW and higher mean ponderal index, respectively. Findings highlight the importance of considerations of seafood subtype in similar investigations.

Disproportionate fetal growth and the risk for congenital cerebral palsy in singleton births.

ObjectiveTo investigate the association between proportionality of fetal and placental growth measured at birth and the risk for congenital cerebral palsy (CP).Study DesignWe identified all live-born singletons born in Denmark between 1995 and 2003 and followed them from 1 year of age until December 31st, 2008. Information on four indices of fetal growth: ponderal index, head circumference/ abdominal circumference ratio, cephalization index and birth weight/ placenta weight ratio was collected. Cox proportional hazards regression models were used to estimate adjusted hazard ratios (aHR) and 95% confidence intervals (CI). All measurements were evaluated as gestational age and sex specific z-scores and in z-score percentile groups, adjusted for potential confounders, and stratified on gestational age groups (<32, 32-36, 37-38, 39, 40, ≥41 weeks).ResultsWe identified 503,784 singleton births, of which 983 were confirmed cases of CP. Head/ abdominal circumference ratio (aHR:1.12; 95%CI:1.07-1.16) and cephalization index (aHR:1.14; 95%CI:1.11-1.16) were associated with the risk of CP irrespective of gestational age. Birth weight-placental weight ratio was also associated with CP in the entire cohort (aHR:0.90; 95%CI:0.83-0.97). Ponderal index had a u-shaped association with CP, where both children with low and high ponderal index were at higher risk of CP.ConclusionsCP is associated with disproportions between birth weight, birth length, placental weight and head circumference suggesting pre and perinatal conditions contribute to fetal growth restriction in children with CP.

The relationship between maternal, placental and newborn parameters

Objective: The aim of this study was to investigate the relationship between maternal, placental and newborn parameters. Methods: The sample consisted of 104 women who had agreed to participate in the research and whose pregnancy had reached 37 weeks or over. Only singleton births were included. The placental and newborn parameters were measured after delivery. Results: We found that the mean placental weight was 563.6±135.65 grs, and the mean of newborn weight was 3358±487.58 grs. The placental weight was significantly positively correlated with infant's birth weight (p=.000), infant's length (p=.024), maternal weight before pregnancy (p=.021), maternal weight on last day of pregnancy ( p=.002), and maternal Body Mass Index (BMI) on the last day of pregnancy (p=.015) The placental weight of smoker during pregnancy was 628.82±107.40 grams; placental weight of non-smoker during pregnancy was 550.91±137.44 grams, and the difference was statistically significant (p=.007). The infant's weight was significantly negatively correlated with the number of cigarettes smoked each day during pregnancy (p=.042). It was also significantly positively correlated with the infant's placental weight (p=.000), length (p=.000), head circumference (p=.004), chest circumference (p=.000), and gestational week ( p=.001). In addition to, it was significantly positively correlated with the maternal weight before pregnancy (p=.002), maternal BMI before pregnancy (p=.007), maternal weight on the last day of pregnancy ( p=.000), and maternal BMI on the last day of pregnancy ( p=.002). Conclusion: In conclusion, we determined that the placenta is an indicator of fetal growth. Also, maternal BMI has an effect on the newborn's weight. Maternal smoking during pregnancy was associated with an increase in placental weight as well as a decrease in an infant's weight.

Factors associated with ultrasound-aided detection of suboptimal fetal growth in a malaria-endemic area in Papua New Guinea.

BackgroundFetal growth restriction (FGR) is associated with increased infant mortality rates and ill-health in adulthood. Evaluation of fetal growth requires ultrasound. As a result, ultrasound-assisted evaluations of causes of FGR in malaria-endemic developing countries are rare. We aimed to determine factors associated with indicators of abnormal fetal growth in rural lowland Papua New Guinea (PNG).MethodsWeights and growth of 671 ultrasound-dated singleton pregnancies (<25 gestational weeks) were prospectively monitored using estimated fetal weights and birthweights. Maternal nutritional status and haemoglobin levels were assessed at enrolment, and participants were screened for malaria on several occasions. FGR was suspected upon detection of an estimated fetal weight or birthweight <10th centile (small-for-gestational age) and/or low fetal weight gain, defined as a change in weight z-score in the first quartile. Factors associated with fetal weight and fetal weight gain were additionally assessed by evaluating differences in weight z-scores and change in weight z-scores. Log-binomial and linear mixed effect models were used to determine factors associated with indicators of FGR.ResultsSGA and low weight gain were detected in 48.3% and 37.0% of pregnancies, respectively. Of participants, 13.8%, 21.2%, and 22.8% had a low mid-upper arm circumference (MUAC, <22 cms), short stature (<150 cms) and anaemia (haemoglobin <90 g/L) at first antenatal visit. 24.0% (161/671) of women had at least one malaria infection detected in peripheral blood. A low MUAC (adjusted risk ratio [aRR] 1.51, 95% CI 1.29, 1.76, P < 0.001), short stature (aRR 1.27, 95% CI 1.04, 1.55, P = 0.009), and anaemia (aRR 1.27, 95% CI 1.06, 1.51, P = 0.009) were associated with SGA, and a low body mass index was associated with low fetal weight gain (aRR 2.10, 95% CI 1.62, 2.71, P < 0.001). Additionally, recent receipt of intermittent preventive treatment in pregnancy was associated with increased weight z-scores, and anaemia with reduced change in weight z-scores. Malaria infection was associated with SGA on crude but not adjusted analyses (aRR 1.13, 95% CI 0.95, 1.34, P = 0.172).ConclusionMacronutrient undernutrition and anaemia increased the risk of FGR. Antenatal nutritional interventions and malaria prevention could improve fetal growth in PNG.

Overview of Disinfection By-products and Associated Health Effects.

The presence of chemical compounds formed as disinfection by-products (DBPs) is widespread in developed countries, and virtually whole populations are exposed to these chemicals through ingestion, inhalation, or dermal absorption from drinking water and swimming pools. Epidemiological evidence has shown a consistent association between long-term exposure to trihalomethanes and the risk of bladder cancer, although the causal nature of the association is not conclusive. Evidence concerning other cancer sites is insufficient or mixed. Numerous studies have evaluated reproductive implications, including sperm quality, time to pregnancy, menstrual cycle, and pregnancy outcomes such as fetal loss, fetal growth, preterm delivery, and congenital malformation. The body of evidence suggests only minor effects from high exposure during pregnancy on fetal growth indices such as small for gestational age (SGA) at birth. Populations highly exposed to swimming pools such as pool workers and professional swimmers show a higher prevalence of respiratory symptoms and asthma, respectively, although the direction of the association, and thus causality, is not clear among professional swimmers. The risk of asthma, wheezing, eczema, and other respiratory outcomes among children attending swimming pools has been the object of extensive research. Early studies suggested a positive association, while subsequent larger studies found no correlations or showed a protective association. Future research should develop methods to evaluate the effects of the DBP mixture and the interaction with personal characteristics (e.g., genetics, lifestyle), clarify the association between swimming pools and respiratory health, evaluate the occurrence of DBPs in low- and middle-income countries, and evaluate outcomes suggested by animal studies that have not been considered in epidemiological investigations.

Fetal growth and preterm birth in children exposed to maternal or paternal rheumatoid arthritis: a nationwide cohort study.

To assess indicators of fetal growth and risk of preterm birth in children of parents with rheumatoid arthritis (RA). Through linkage of Danish national registries, we identified all children born in Denmark between 1977 and 2008. We used general linear regression models to estimate mean differences in indicators of fetal growth among children with a parent with RA compared to unexposed children. Odds ratios (ORs) and 95% confidence intervals (95% CIs) of preterm birth were calculated using a logistic regression model. Of the 1,917,723 children included, a total of 13,556 children were exposed to maternal RA or maternal preclinical RA. Children exposed to maternal RA (n = 2,101) had approximately similar length, head circumference, and abdominal circumference at birth compared with children of mothers without RA. Birth weight was 87 gm lower (mean difference -87.04 gm [95% CI -111.23, -62.84]) and placenta weight was 14 gm lower (-13.45 gm [95% CI -21.46, -5.43]) than those in children of mothers without RA. Rather similar results were found in children exposed to maternal preclinical RA (n = 11,455). Compared with unexposed children, a higher risk of preterm birth was found in children exposed to maternal RA (OR 1.48 [95% CI 1.20, 1.84]) and preclinical RA (OR 1.32 [95% CI 1.07, 1.64]). No associations were found with paternal RA. Children exposed to either maternal RA or maternal preclinical RA are more often born preterm. However, indicators of fetal growth measured at birth were only slightly lower than those in unexposed children.

Gender-specific relationship between prenatal exposure to phthalates and intrauterine growth restriction.

No study has examined the association between prenatal phthalate exposure and intrauterine growth retardation (IUGR). This study aimed to investigate whether prenatal exposure to phthalates was associated with increased risk of IUGR. A total of 126 mother-newborn pairs, including 42 IUGR cases and 84 control newborns and their mothers, were enrolled in this case-control study. Spot urine samples were collected during the third trimester of pregnancy, and 5 phthalate metabolites (mono-n-butyl phthalate (MBP), monomethyl phthalate (MMP), mono-2-ethylhexyl phthalate (MEHP), mono(2-ethyl-5-oxohexyl) phthalate (MEOHP), and mono(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP)) were measured. Concentrations of MMP, MEHHP, MEOHP, and SumDEHP (MEHP, MEHHP, and MEOHP) were significantly higher in IUGR cases than in normal controls. In all subjects, urinary concentrations of MEHHP and MEOHP were significantly inversely associated with fetal growth indicators (birth weight and Quetelet's index). When mothers were stratified by infant sex, MEHHP and MEOHP concentrations were still negatively associated with fetal growth indicators, while no significant association was observed in females. In addition, exposure-response relationships were observed between MEHHP/SumDEHP concentrations in maternal urine and IUGR. Prenatal exposure to phthalates was associated with increased risk of IUGR, and male newborns were more sensitive to phthalates than females.

PPO.58 Outcome of Pregnancy with Low PAPP-A

BackgroundPAPP-A is a biochemical marker in first trimester screening undertaken at 11–13 weeks gestation. Studies have shown that low levels of it (<0.4 MoM) are descriptive of poor early placentation...

Blockade of the renin angiotensin system abolishes age‐dependent hypertension in female intrauterine growth restricted rats in the absence of an enhanced sensitivity to acute angiotensin II (1085.2)

Low birth weight (LBW) as an indicator of poor fetal growth is a risk factor for hypertension. Placental insufficiency induces intrauterine growth restriction (IUGR) in the female rat indicative of LBW. Female IUGR rats exhibit an enhanced sensitivity to acute angiotensin II (Ang II) while remaining normotensive under basal conditions at 4 months of age. Yet, female IUGR rats develop hypertension by 12 month of age. Thus, this study tested the hypothesis that the renin angiotensin system (RAS) contributes to the etiology of age‐dependent hypertension in the female IUGR rat. At 12 months of age rats were treated with vehicle or the ACE inhibitor, enalapril (250 mg/L in drinking water ad libitum), for 2 weeks then mean arterial pressure (MAP) was measured in conscious, chronically instrumented rats. MAP was significantly higher in untreated IUGR versus untreated control rats (134±3 vs. 117±4 mmHg, P&lt;0.05; respectively); enalapril abolished the difference in MAP (118±2 vs. 113±1 mmHg; respectively). Acute infusion (20 min) of Ang II (100 ng/kg/min) increased MAP in all groups (155±3, 164±2, 148±1, 154±2 mmHg; control untreated, IUGR untreated, control treated &amp; IUGR treated; respectively). Yet, the increase in MAP to Ang II was not enhanced in IUGR versus control counterpart. Thus, these data suggest that the RAS contributes to age‐dependent hypertension in the female IUGR in the absence of enhanced sensitivity to Ang II.Grant Funding Source: Supported by HL074927, HL51971, 12POST11980021

Fetal Growth in Pregnancies Conceived after Gastric Bypass Surgery in Relation to Surgery-to-Conception Interval: A Danish National Cohort Study

ObjectiveTo describe early and late fetal growth in pregnancies conceived after gastric bypass surgery in relation to time from surgery to conception of pregnancy.MethodsNational cohort study on 387 Danish women, who had laparoscopic or open gastric bypass surgery prior to a singleton pregnancy in which first trimester screening was performed between January 2008 and June 2011. Data were derived from national registers (Danish National Registry of Patients and Danish National Birth Registry, Pregnancy Complications and Abortion - clinical quality database (PreCAb) and the Danish Fetal Medicine Database). Main outcome measures were early and late fetal growth in relation to time from bariatric surgery to conception of the pregnancy. Early fetal growth was expressed as “Fetal Growth Index”: the ratio between the estimated number of days from first trimester ultrasound to second trimester ultrasound biometries and the actual calender time elapsed in days. Late fetal growth was expressed as the observed versus expected birthweight according to gestational age (GA).ResultsThe surgery-to-conception interval ranged from 3 to 1851 days with a mean value of 502 (SD, 351) days. The mean “fetal growth index” was 0.99 (SD, 0.02) days/day and thus significantly lower than in the background population (mean, 1.04 (SD, 0.09) days/day, p<0.0001).The proportion of infants being small for gestational age was 18.8% and the proportion of large for gestational age infants was 6.7%. The correlation coefficients between surgery-to-conception time and “fetal growth index” and birthweight according to GA were 0.01 (p = 0.8) and 0.04 (p = 0.4), respectively.ConclusionFetal growth index was lower than reported in the background population. No correlation was found between the surgery-to-conception interval and early or late fetal growth in pregnancies conceived after gastric bypass surgery.

Ultrasonographic Evaluation of Equine Fetal Growth Throughout Gestation in Normal Mares Using a Convex Transducer

ABSTRACTIt has not been common to perform regular ultrasound examination of the fetus in equine practice, due to the increasing volume of the uterus caused by fetal development. The convex three-dimensional transducer is bulb-shaped and is able to observe wide areas. In addition, its operation is simple, making it easy to create appropriate angles for various indices using a transrectal approach. The aim of this study was to measure Thoroughbred fetal growth indices throughout gestation using a convex transducer and to clarify the detectable period of some indices for clinical use. We demonstrated changes in fetal indices, such as crown rump length (CRL), fetal heart rate (FHR), fetal eye and kidney and the combined thickness of uterus and placenta (CTUP). CTUP increased from 30 weeks of gestation, and FHR peaked at 8 weeks and then decreased to term. CRL could be observed until 13 weeks due to its wide angle, longer than in previous reports. Fetal eye and kidney could be observed from 10 and 28 weeks, respectively, and these increased with pregnancy progress. The present results showed the advantage of transrectal examination using a convex transducer for evaluation of normal fetal development. Although ultrasonographic examination in mid- to late-gestation is not common in equine reproductive practice, our comprehensive results would be a useful basis for equine pregnancy examination.

Effect of treatment of vitamin D deficiency and insufficiency during pregnancy on fetal growth indices and maternal weight gain: a randomized clinical trial

ObjectiveTo determine whether treatment of low serum vitamin D in pregnant women improves fetal growth indices. Study designIn this open-label randomized clinical trial, 130 Iranian pregnant women (24–26 weeks of gestation) with vitamin D deficiency or insufficiency [25(OH)D <30ng/ml] were divided at random into an intervention group and a control group. The control group received 200mg calcium plus a multivitamin (containing vitamin D3 400U) each day, and the intervention group received 200mg calcium plus a multivitamin (containing vitamin D3 400U) each day, plus vitamin D3 (50,000U) each week for 8 weeks. At delivery, maternal and cord blood 25(OH)D levels, maternal weight gain, neonatal length, neonatal weight and neonatal head circumference were compared between two groups. Serum vitamin D was measured using enzyme-linked immunosorbent assay. A multivariate regression analysis was performed to examine the independent effect of maternal vitamin D level on fetal growth indices. ResultsMean (±standard deviation) length (intervention group: 49±1.6cm; control group: 48.2±1.7cm; p=0.001), head circumference (intervention group: 35.9±0.7cm; control group: 35.3±1.0cm; p=0.001) and weight (intervention group: 3429±351.9g; control group: 3258.8±328.2g; p=0.01) were higher in the intervention group compared with the control group. Mean maternal weight gain was higher in the intervention group compared with the control group (13.3±2.4kg vs 11.7±2.7kg; p=0.006). Multivariate regression analysis for maternal weight gain, neonatal length, neonatal weight and neonatal head circumference showed an independent correlation with maternal vitamin D level. ConclusionTreatment of low serum vitamin D during pregnancy improves fetal growth indices and maternal weight gain.

The Association between First Trimester Maternal Exposure to Air Pollutants and Indicators of Fetal Growth in Mexico City

Background: Maternal exposures to air pollution in early pregnancy may affect subsequent fetal growth. Aims: We examined the association between first trimester maternal exposure to air pollution a...

Factors relating to pregnancy and birth and the risk of childhood brain tumors: Results from an Australian case-control study

Childhood brain tumors (CBT) are the leading cause of cancer death in children, yet their causes are largely known. This study investigated the association between maternal and birth characteristics and risk of CBT. Cases families were recruited from all 10 Australian pediatric oncology centers between 2005 and 2010. Control families were recruited via random-digit dialing, frequency matched to cases on the basis of child's age, sex, and State of residence. Maternal and birth characteristics of children were ascertained by questionnaires. Odds ratios (ORs) and 95% confidence intervals (CI) were estimated using unconditional logistic regression, adjusting for relevant confounders. For this analysis, data on 319 case children and 1,079 control children were available. No association was found between risk of CBT and birth weight, fetal growth, birth order, gestational age, or maternal body mass index. The ORs for inadequate and excessive maternal gestational weight gain (GWG) (Institute of Medicine 2009 guidelines) were 1.8 (95% CI 1.2-2.6) and 1.4 (95% CI 1.0-2.1), respectively; similar findings for GWG were seen across categories of child's age, fetal growth, maternal body mass index and height, maternal smoking, and parental education. Risk of low grade glioma appeared increased with preterm birth (OR 1.6 (95% CI 0.8-3.1) and admission to neonatal intensive care (NICU) for >2 days (OR 1.7, 95% CI 0.9-3.6). We found little evidence of associations between risk of CBT and most birth characteristics. The associations we observed with GWG, prematurity and NICU admission require corroboration in other studies.

Invited Commentary: The Incremental Value of Customization in Defining Abnormal Fetal Growth Status

Reference tools based on birth weight percentiles at a given gestational week have long been used to define fetuses or infants that are small or large for their gestational ages. However, important deficiencies of the birth weight reference are being increasingly recognized. Overwhelming evidence indicates that an ultrasonography-based fetal weight reference should be used to classify fetal and newborn sizes during pregnancy and at birth, respectively. Questions have been raised as to whether further adjustments for race/ethnicity, parity, sex, and maternal height and weight are helpful to improve the accuracy of the classification. In this issue of the Journal, Carberry et al. (Am J Epidemiol. 2013;178(8):1301-1308) show that adjustment for race/ethnicity is useful, but that additional fine tuning for other factors (i.e., full customization) in the classification may not further improve the ability to predict infant morbidity, mortality, and other fetal growth indicators. Thus, the theoretical advantage of full customization may have limited incremental value for pediatric outcomes, particularly in term births. Literature on the prediction of short-term maternal outcomes and very long-term outcomes (adult diseases) is too scarce to draw any conclusions. Given that each additional variable being incorporated in the classification schemeincreases complexity and costs in practice, the clinical utility of full customization in obstetric practice requires further testing.

PP001. The vascular tree during pregnancy and at follow-up – A longitudinal study of maternal vascular function

Normal maternal vascular function and optimal cardiovascular adaptation to the increasing demands of pregnancy is a prerequisite for a successful outcome of pregnancy. How different levels of the vascular tree react and interact during pregnancy has not been fully investigated previously but may be determined by genetic as well as maternal, fetal and environmental factors. To investigate how different levels of vascular function change during the course of pregnancy and relate these levels to each other. Healthy non smoking women with singleton pregnancies and a viable embryo recorded at the ultrasound departments of UltraGyn Stockholm, Sweden were recruited. The following cardiovascular examinations were performed: examination of structural changes of the heart: Echocardiography of the heart with Doppler examination and tissue Doppler. Examination of macrocirculation, vessel structure and function plus endothelial function: Intima-media thickness of the common carotid artery, pulse wave velocity, central blood pressure and flow mediated vasodilation. Examination of microvascular function in the skin and endothelial function: total circulation of the skin and capillary flow in nails. The microcirculation before, during and after iontophoresis with nitroprussid and acetylcholine. The investigations were performed in gestational week 11-14, 22-24, 36 and 9 months post partum. In total 35 participants had a normal course of pregnancy. Curves of the development of the various cardiovascular variables will be presented according to gestational age and their place in the vascular tree. These curves will be used to investigate how various determinants such as blood pressure, fetal growth and body mass index, as well as fetal sex affects and are affected by cardiovascular function in pregnancy.

Assessment of fetal tridimensional cerebellar volumes between genders

ABSTRACT Introduction: The object of this study was to assess the tridimensional cerebellar volume between genders and its correlation to other fetal growth parameters indices. Methods: The author carried out a cross-sectional and prospective study involving 125 normal pregnant women from 22 to 36 weeks of gestation. The assessment of fetal cerebellar volume was performed through Virtual Organ Computer-aided Analysis. The author also assessed other biometric fetal growth indices: biparietal diameter, occipitofrontal diameter, abdominal circumference, head circumference, femur length, anteroposterior cisterna magna diameter, lateral ventricle atria width and estimated fetal weight and its correla -tion to cerebellar volume. The Mancova analysis and Pearson’s correlation coefficient were used with gestational age as independent variable and cerebellar volume as dependent variable. Results: The results showed highly correlating to gestational age, biparietal diameter, occipito-frontal diameter, head circumference, femur length and estimated fetal weight (r-value above 0.90 and p<0.0001). Comparison between gen-ders did not show any significant difference in fetal cerebellar volume throughout pregnancy. Conclusions: The assessment of tridimensional cerebellar volume showed no difference between genders, but there was increasing throughout the pregnancy (p<0.0001). Key words: cerebellar volume, tridimensional ultrasound, fetal gender.

IGF2 DNA methylation is a modulator of newborn’s fetal growth and development

The insulin-like growth factor 2 (IGF2) gene, located within a cluster of imprinted genes on chromosome 11p15, encodes a fetal and placental growth factor affecting birth weight. DNA methylation variability at the IGF2 gene locus has been previously reported but its consequences on fetal growth and development are still mostly unknown in normal pediatric population. We collected one hundred placenta biopsies from 50 women with corresponding maternal and cord blood samples and measured anthropometric indices, blood pressure and metabolic phenotypes using standardized procedures. IGF2/H19 DNA methylation and IGF2 circulating levels were assessed using sodium bisulfite pyrosequencing and ELISA, respectively. Placental IGF2 (DMR0 and DMR2) DNA methylation levels were correlated with newborn’s fetal growth indices, such as weight, and with maternal IGF2 circulating concentration at the third trimester of pregnancy, whereas H19 (DMR) DNA methylation levels were correlated with IGF2 levels in cord blood. The maternal genotype of a known IGF2/H19 polymorphism (rs2107425) was associated with birth weight. Taken together, we showed that IGF2/H19 epigenotype and genotypes independently account for 31% of the newborn’s weight variance. No association was observed with maternal diabetic status, glucose concentrations or prenatal maternal body mass index. This is the first study showing that DNA methylation at the IGF2/H19 genes locus may act as a modulator of IGF2 newborn’s fetal growth and development within normal range. IGF2/H19 DNA methylation could represent a cornerstone in linking birth weight and fetal metabolic programming of late onset obesity.

Differential Fetal Responses to Maternal Nutrient Restriction: A Population Variance Approach.

Recent studies have demonstrated that, although important, birth weight alone is an insufficient indicator of fetal growth and postnatal health and well-being. Using the undernourished sheep model, it is widely accepted that maternal nutrient restriction (NR) results in offspring that are smaller at birth than counterparts from adequately fed ewes. However, closer examination of these cohorts reveals a highly variable response to maternal nutrient stress, as might be expected in an outbred animal. Our objective was to identify and further investigate fetuses benefiting from a positive adaptive response to this nutritional stress, as evidenced by normal fetal weight, compared to those exhibiting intrauterine growth restriction (IUGR). To identify subpopulations of ewes able to support normal fetal growth despite inadequate nutrition, multiparous Suffolk ewes were made pregnant by transfer of a single embryo into the uterus on Day 5.5 post-estrus. Pregnancy was confirmed by ultrasound on Day 28. Beginning on Day 35 of pregnancy and continuing throughout the study, ewes were fed 50% of the NRC requirements. An additional group of ewes received 100% of their NRC recommended intake throughout the study to serve as a control. On Day 125 of pregnancy, ewes were necropsied and fetal and placental tissues were collected. Results of subsequent analyses identified unique organ specific patterns in gene expression segregating these three distinct fetal sub-populations. Interestingly, in some instances NR non-IUGR fetuses exhibit gene expression patterns similar to control fed animals, while in other cases both NR non-IUGR and IUGR fetuses exhibit a similar pattern of gene expression that is vastly different than that of fetuses from control fed ewes. These intriguing results highlight the need for a more comprehensive assessment of the intrauterine environment during fetal development to predict short- and long-term health of the offspring. This knowledge will prove useful for identifying windows of potential intervention. Further, these studies highlight the value of alternative outbred animal models such as the sheep for understanding dynamic processes regulating fetal growth and development.

Effect of high parity on occurrence of some fetal growth indices: a cohort study

The objective of this retrospective cohort study was to explore the potential causal relation between parity and fetal growth indices, including low birth weight (LBW), macrosomia, and prematurity. The study was nested on a community trial in a city in Oman. The study analyzed 1939 pregnancies among 479 participants. Of these, 944 pregnancies (48.7%) were high parity (≥5). Obtained newborns with outcomes of interest were as follows: 191 LBW, 34 macrosomic, and 69 premature. Associations were measured using multilevel logistic regression modeling. Compared to low parity (LP, defined as <5), high parity was found to be associated with less risk of LBW (relative risk [RR] = 0.76; 95% confidence interval [CI]: 0.44–1.1) and prematurity (RR = 0.82; 95% CI: 0.54–1.27), but greater risk of macrosomia (RR = 1.8; 95% CI: 1.2–2.4). This study provides evidence that with increasing parity, risks of LBW and prematurity decrease, while risk of macrosomia increases.