Fetal Growth Indices Research Articles

Glyphosate exposure in pregnancy and shortened gestational length: a prospective Indiana birth cohort study

BackgroundGlyphosate (GLY) is the most heavily used herbicide worldwide but the extent of exposure in human pregnancy remains unknown. Its residues are found in the environment, major crops, and food items that humans, including pregnant women, consume daily. Since GLY exposure in pregnancy may also increase fetal exposure risk, we designed a birth-cohort study to determine exposure frequency, potential exposure pathways, and associations with fetal growth indicators and pregnancy length.MethodUrine and residential drinking water samples were obtained from 71 women with singleton pregnancies living in Central Indiana while they received routine prenatal care. GLY measurements were performed using liquid chromatography-tandem mass spectrometry. Demographic and survey information relating to food and water consumption, stress, and residence were obtained by questionnaire. Maternal risk factors and neonatal outcomes were abstracted from medical records. Correlation analyses were used to assess relationships of urine GLY levels with fetal growth indicators and gestational length.ResultsThe mean age of participants was 29 years, and the majority were Caucasian. Ninety three percent of the pregnant women had GLY levels above the limit of detection (0.1 ng/mL). Mean urinary GLY was 3.40 ng/mL (range 0.5–7.20 ng/mL). Higher GLY levels were found in women who lived in rural areas (p = 0.02), and in those who consumed > 24 oz. of caffeinated beverages per day (p = 0.004). None of the drinking water samples had detectable GLY levels. We observed no correlations with fetal growth indicators such as birth weight percentile and head circumference. However, higher GLY urine levels were significantly correlated with shortened gestational lengths (r = − 0.28, p = 0.02).ConclusionsThis is the first study of GLY exposure in US pregnant women using urine specimens as a direct measure of exposure. We found that > 90% of pregnant women had detectable GLY levels and that these levels correlated significantly with shortened pregnancy lengths. Although our study cohort was small and regional and had limited racial/ethnic diversity, it provides direct evidence of maternal GLY exposure and a significant correlation with shortened pregnancy. Further investigations in a more geographically and racially diverse cohort would be necessary before these findings could be generalized.

Cumulative exposure to environmental pollutants during early pregnancy and reduced fetal growth: the Project Viva cohort

BackgroundReduced fetal growth is associated with perinatal and later morbidity. Prenatal exposure to environmental pollutants is linked to reduced fetal growth at birth, but the impact of concomitant exposure to multiple pollutants is unclear. The purpose of this study was to examine interactions between early pregnancy exposure to cigarette smoke, traffic pollution, and select perfluoroalkyl substances (PFASs) on birth weight-for-gestational age (BW/GA).MethodsAmong 1597 Project Viva mother-infant pairs, we assessed maternal cigarette smoking by questionnaire, traffic pollution at residential address by black carbon land use regression model, and plasma concentration of select PFASs in early pregnancy. We calculated sex-specific BW/GA z-scores, an index of fetal growth, from national reference data. We fit covariate-adjusted multi-pollutant linear regression models and examined interactions between exposures, using a likelihood-ratio test to identify a best-fit model.ResultsTwo hundred six (13%) mothers smoked during pregnancy. Mean [standard deviation (SD)] for black carbon was 0.8 (0.3) μg/m3, perfluorooctane sulfonate (PFOS) was 29.1 (16.5) ng/mL, and BW/GA z-score was 0.19 (0.96). In the best-fit model, BW/GA z-score was lower in infants of mothers exposed to greater black carbon [− 0.08 (95% CI: -0.15, − 0.01) per interquartile range (IQR)]. BW/GA z-score (95% CI) was also lower in infants of mothers who smoked [− 0.09 (− 0.23, 0.06)] or were exposed to greater PFOS [− 0.03 (− 0.07, 0.02) per IQR], although confidence intervals crossed the null. There were no interactions between exposures. In secondary analyses, instead of PFOS, we examined perfluorononanoate (PFNA) [mean (SD): 0.7 (0.4) ng/mL], a PFAS more closely linked to lower BW/GA in our cohort. The best-fit multi-pollutant model included positive two-way interactions between PFNA and both black carbon and smoking (p-interactions = 0.03).ConclusionsConcurrent prenatal exposures to maternal smoking, black carbon, and PFOS are additively associated with lower fetal growth, whereas PFNA may attenuate associations of smoking and black carbon with lower fetal growth. It is important to examine interactions between multiple exposures in relation to health outcomes, as effects may not always be additive and may shed light on biological pathways.

213: Comparison of buprenorphine versus methadone exposure in utero on fetal growth indices and neonatal abstinence syndrome

213: Comparison of buprenorphine versus methadone exposure in utero on fetal growth indices and neonatal abstinence syndrome

The combined xenoestrogenic activity of perfluorinated alkyl acids in pregnant women and indices of fetal growth

Research shows cigarette smoking is associated with lower academic performance among youth. This study examines how initiating e-cigarette use is associated with subsequent academic performance. Data from Waves 2–4 youth and parent surveys of the Population Assessment of Tobacco and Health (PATH) Study were analyzed. Youth (12–15 years old) who reported never using any tobacco products at Wave 2 were included in the analysis (n = 4960). Initiation of e-cigarettes and cigarettes was assessed at Wave 3. Weighted multivariable linear regression models were tested to assess the association between e-cigarette and cigarette initiation at Wave 3 and academic performance at Wave 4, controlling for covariates at Wave 2. At Wave 3, 4.3% and 1.9% of youth initiated e-cigarette and cigarette use, respectively. Youth who initiated e-cigarette use at Wave 3 had lower academic performance at Wave 4, compared to those who did not initiate e-cigarette use (adjusted regression coefficient [ARC] -0.22, 95% confidence interval [CI] -0.43, −0.02). Initiating cigarettes was also associated with lower academic performance (ARC -0.51, 95% CI -0.84, −0.18). Results indicate that e-cigarette use initiation is associated with lower subsequent academic performance, independent from the association between cigarette use initiation and lower academic performance among U.S. youth. Future research needs to examine whether preventing youth e-cigarette and cigarette use can lead to improvement in academic performance.

The combined xenoestrogenic and xenoandrogenic activities of serum lipophilic POPs in Danish pregnant women and indices of fetal growth

The combined xenoestrogenic and xenoandrogenic activities of serum lipophilic POPs in Danish pregnant women and indices of fetal growth

Human Placental Arterial Distensibility, Birth Weight, and Body Size Are Positively Related to Fetal Homocysteine Concentration.

Methionine demethylation during metabolism generates homocysteine (Hcy) and its remethylation requires folate and cobalamin. Elevated Hcy concentrations are associated with vascular-related complications of pregnancy, including increased vascular stiffness, predictive of clinical vascular disease. Maternal and fetal total Hcy (tHcy) concentrations are positively related, yet the influence of Hcy on fetoplacental vascular function in normal pregnancy has not been examined. We hypothesized that Hcy alters fetoplacental vascular characteristics with influences on fetal growth outcomes. We investigated (1) placental chorionic plate artery distensibility and neonatal blood pressure in relation to umbilical plasma tHcy; (2) relationships between cord venous (CV) and cord arterial (CA) plasma tHcy, folate, and cobalamin concentrations; and (3) tHcy associations with birth weight and anthropometric measurements of body size as indices of fetal growth in normal pregnancies with appropriate weight-for-gestational age newborns. Maternal plasma tHcy, folate, and cobalamin concentrations were consistent with published data. Placental chorionic plate artery distensibility index (β; measure of vessel stiffness) was inversely related to CA tHcy, yet neonatal blood pressure was not significantly affected. CV and CA tHcy concentrations were positively related and CV tHcy negatively related to CV cobalamin but not folate. CV tHcy concentration positively related to birth weight, corrected birth weight percentile, length, head circumference, and mid-arm circumference of newborns. CV cobalamin was inversely related to fetal growth indices but not to folate concentration. Our study demonstrates a potential relationship between fetal tHcy and placental artery distensibility, placing clinical relevance to cobalamin in influencing Hcy concentration and maintaining low vascular resistance to facilitate nutrient exchange favorable to fetal growth.

Indicators of fetal growth and adult liver enzymes: the Bogalusa Heart Study and the Cardiovascular Risk in Young Finns Study.

Despite the interest in the relationship of fetal exposures to adult cardiovascular disease, few studies have examined indicators of adult fatty liver disease as an outcome. Previous results are inconsistent, and indicate possible variation by sex. Adult liver enzymes [γ-glutamyl transferase (GGT), alanine transaminase (ALT) and aspartase transaminase (AST)] were measured in two cohort studies: the Bogalusa Heart Study (BHS; n=1803) and the Cardiovascular Risk in Young Finns (YF; n=3571) study, which also had ultrasound measures of liver fat (n=2546). Predictors of dichotomized (clinical cut-offs) and continuous (within the reference range) liver enzymes included low birthweight (4000 g), small-for-gestational-age (birthweight 90th percentile), and preterm birth. Multiple logistic and linear regression were conducted, adjusted for medical, behavioral and socioeconomic indicators. Interactions with sex were also examined. In BHS, birth measures were not strongly associated with clinically high levels of liver enzymes, and within the reference range measures of reduced growth were associated with increased AST in women. In the YF study, at least one marker of reduced growth was associated with higher GGT, higher ALT and higher AST (in women). Probable fatty liver on ultrasound was associated with low birthweight (2.41, 1.42-4.09) and preterm birth (2.84, 1.70-4.76). These results suggest a link between birth parameters and adult fatty liver, but encourage consideration of population variation in these relationships.

Congenital Heart Defects and Indices of Placental and Fetal Growth in a Nationwide Study of 924 422 Liveborn Infants.

Congenital heart defects (CHDs) have been associated with placental anomalies. The nature and the consequences of this association remain poorly understood. We aimed to estimate the associations between all major subtypes of CHD and placental weight at birth, and the association between placental weight and measures of both overall and cerebral growth in fetuses with CHD, as well. We included all 924 422 liveborn Danish singletons, 1997 to 2011. CHD was present in 7569. We compared mean differences in placental weight z score between newborns with CHD and newborns without CHD by multivariable linear regression adjusted for potential confounders. CHD was associated with a mean z score difference of -0.04 (95% confidence interval, -0.07 to -0.02). Some subtypes were associated with smaller placental size at birth: tetralogy of Fallot, -0.45 (95% confidence interval, -0.58 to -0.31); double-outlet right ventricle, -0.48 (95% confidence interval, -0.87 to -0.10); major ventricular septal defects, -0.41 (95% confidence interval, -0.52 to -0.29). Placental weight z score was associated with birth weight and head circumference z scores in all subtypes. In the 3 mentioned subtypes, the mean deviations from the population mean head circumference and birth weight z scores were reduced by up to 66% with adjustment for placental weight z score. Three subtypes of CHD were associated with lower placental weight, and placental weight was associated with measures of both overall growth and cerebral growth in fetuses with all subtypes of CHD. In certain subtypes, the described deviations in fetal growth were reduced by up to two-thirds after adjustment for placental weight z score.

Maternal serum levels of perfluoroalkyl substances and organochlorines and indices of fetal growth: a Scandinavian case\u2013cohort study

Background:The associations between prenatal exposure to endocrine disruptive chemicals (EDCs) and fetal growth are inconsistent, and few studies have considered small-for-gestational-age (SGA) birth as an outcome. Our current study of Scandinavian parous women aimed to address these inconsistencies and gaps in the literature.Methods:This case–cohort study included 424 mother–child pairs who participated in a prospective, multi-center study of parous women in Norway (Trondheim and Bergen) and Sweden (Uppsala). We used linear and logistic regression with 95% confidence intervals (CIs) to analyze the associations between two perfluoroalkyl substances (PFASs) and five organochlorines (OCs) from early second trimester and indices of fetal growth.Results:Among Swedish women, prenatal exposure to perfluorooctanoate (PFOA), polychlorinated biphenyl (PCB) 153 and hexachlorobenzene (HCB) were associated with higher odds for SGA birth. We found stronger associations among Swedish male offspring. In the Norwegian cohort, we found no significant associations between EDC exposure and indices of fetal growth.Conclusions:Some populations may be more vulnerable to EDCs, possibly due to differences in exposure levels, exposure sources and/or modifiable lifestyle factors. Male offspring may be more vulnerable to endocrine disruption.

Fetal Hemodynamics and Fetal Growth Indices by Ultrasound in Late Pregnancy and Birth Weight in Gestational Diabetes Mellitus.

Background:The offspring of women with gestational diabetes mellitus (GDM) are prone to macrosomia. However, birth weight is difficult to be correctly estimated by ultrasound because of fetal asymmetric growth characteristics. This study aimed to investigate the correlations between fetal hemodynamics, fetal growth indices in late pregnancy, and birth weight in GDM.Methods:A total of 147 women with GDM and 124 normal controls (NC) were enrolled in this study. Fetal hemodynamic indices, including the systolic/diastolic ratio (S/D), resistance index (RI), pulsatility index (PI) of umbilical artery (UA), middle cerebral artery (MCA), and renal artery (RA), were collected. Fetal growth indices, including biparietal diameter (BPD), head circumference (HC), abdominal circumference (AC), and femur length, were also measured by ultrasound. Birth weight, newborn gender, and maternal clinical data were collected.Results:The independent samples t-test showed that BPD, HC, and AC were larger in GDM than in NC (P < 0.05). Fetal hemodynamic indices of the UA and MCA were lower (P < 0.05), but those of the RA were higher (P < 0.001) in GDM than in NC. Birth weight was higher in GDM than in NC (P < 0.001). Pearson's correlation analysis showed that hemodynamic indices of the UA were negatively correlated with birth weight, BPD, HC, and AC in both groups (P < 0.05). MCA (S/D, PI, and RI) was negatively correlated with birth weight, HC, and AC in GDM (r = −0.164, −0.206, −0.200, −0.226, −0.189, −0.179, −0.196, −0.177, and − 0.172, respectively, P < 0.05), but there were no correlations in NC (P > 0.05). RA (S/D, PI, and RI) was positively correlated with birth weight in GDM (r = 0.168, 0.207, and 0.184, respectively, P < 0.05), but there were no correlations in NC (P > 0.05).Conclusion:Fetal hemodynamic indices in late pregnancy might be helpful for estimating newborn birth weight in women with GDM.

Maternal creatine in pregnancy: a retrospective cohort study.

To estimate creatine concentrations in maternal plasma and urine, and establish relationships with maternal characteristics, diet and fetal growth. Retrospective cohort study. Lyell McEwin Hospital, Adelaide, Australia. A biobank of plasma and urine samples collected at 13, 18, 30 and 36weeks' gestation from 287 pregnant women from a prospective cohort of asthmatic and non-asthmatic women. Creatine was measured by enzymatic analysis. Change in creatine over pregnancy was assessed using the Friedman test. Linear mixed models regression was used to determine associations between maternal factors and diet with creatine across pregnancy and between creatine with indices of fetal growth at birth. Maternal creatine concentrations, associations between maternal factors and creatine and between creatine and fetal growth parameters. Maternal smoking, body mass index, asthma and socio-economic status were positively and parity negatively associated with maternal plasma and/or urine creatine. Maternal urine creatine concentration was positively associated with birthweight centile and birth length. After adjustment, each μmol/l increase in maternal urinary creatine was associated with a 1.23 (95% CI 0.44-2.02) unit increase in birthweight centile and a 0.11-cm (95% CI 0.03-0.2) increase in birth length. Maternal factors and fetal growth measures are associated with maternal plasma and urine creatine concentrations. Maternal creatine is altered by pregnancy; fetal growth measures are associated with maternal creatine concentrations.

Prenatal exposure to chlordecone, gestational weight gain, and birth weight in a Guadeloupean birth cohort

BackgroundChlordecone is a persistent organochlorine insecticide with well-defined estrogenic properties. It was intensively used in the French West Indies until 1993 to control the banana root borer. Because of the long-term contamination of soils and water, the population is currently exposed to chlordecone through food consumption. Chlordecone has been found in the blood of pregnant women and in cord blood. It has been shown to be an endocrine-disrupting chemical and exposure during pregnancy may affect fetal growth. ObjectivesThe objective of our study was to examine the association between prenatal exposure to chlordecone and fetal growth based on the TIMOUN birth cohort conducted in Guadeloupe, with a focus on the potential modification of this relationship by maternal body mass index (BMI) and gestational weight gain (GWG). MethodsChlordecone was determined in cord plasma at birth in 593 babies. Birth weight was the indicator of fetal growth. Maternal pre-pregnancy BMI and GWG were determined. Adherence to GWG recommendations of the US Institute of Medicine based on maternal pre-pregnancy BMI was assessed. Birth weight was analyzed relative to cord blood chlordecone levels using linear and non-linear regression models. ResultsOverall chlordecone in cord blood was not associated with birth weight, but we found an interaction between chlordecone exposure with GWG and adherence to GWG recommendations. After stratification by GWG, we found a significant U-shaped association between birth weight and chlordecone exposure, within the upper quartiles of GWG or excessive GWG. ConclusionChlordecone exposure may affect fetal growth, particularly when excessive GWG is present.

Urinary phthalate metabolite and bisphenol A associations with ultrasound and delivery indices of fetal growth

Growth of the fetus is highly sensitive to environmental perturbations, and disruption can lead to problems in pregnancy as well as later in life. This study investigates the relationship between maternal exposure to common plasticizers in pregnancy and fetal growth. Participants from a longitudinal birth cohort in Boston were recruited early in gestation and followed until delivery. Urine samples were collected at up to four time points and analyzed for concentrations of phthalate metabolites and bisphenol A (BPA). Ultrasound scans were performed at four time points during pregnancy for estimation of growth parameters, and birthweight was recorded at delivery. Growth measures were standardized to a larger population. For the present analysis we examined cross-sectional and repeated measures associations between exposure biomarkers and growth estimates in 482 non-anomalous singleton pregnancies. Cross-sectional associations between urinary phthalate metabolites or BPA and growth indices were imprecise. However, in repeated measures models, we observed significant inverse associations between di-2-ethylhexyl phthalate (DEHP) metabolites and estimated or actual fetal weight. An interquartile range increase in summed DEHP metabolites was associated with a 0.13 standard deviation decrease in estimated or actual fetal weight (95% confidence interval=−0.23, −0.03). Associations were consistent across different growth parameters (e.g., head circumference, femur length), and by fetal sex. No consistent associations were observed for other phthalate metabolites or BPA. Maternal exposure to DEHP during pregnancy was associated with decreased fetal growth, which could have repercussive effects.

Congenital Heart Defects and Measures of Fetal Growth in Newborns with Down Syndrome or 22q11.2 Deletion Syndrome

To estimate the association between congenital heart defects (CHD) and indices of fetal growth in Down and 22q11.2 deletion syndromes. We established 2 Danish nationwide cohorts of newborn singletons with either Down syndrome (n=670) or 22q11.2 deletion syndrome (n=155), born 1997-2011. In both cohorts, we analyzed the association between CHD, CHD severity, and indices of fetal growth by multivariable linear regression adjusted for potential confounders. We report mean differences in gestational age specific z-scores compared with newborns without CHD. Down syndrome and 22q11.2 deletion syndrome were both associated with lower mean birth weight and head circumference z-scores. We found no association between CHD or CHD severity and indices of fetal growth. In Down syndrome, the association between any CHD and the mean difference in head circumference z-score was 0.03 (95% CI -0.12, 0.18), and the estimate regarding birth weight z-score was 0.09 (95% CI -0.08, 0.25). The corresponding estimates in 22q11.2 deletion syndrome were 0.00 (95% CI -0.33, 0.32) and -0.09 (95% CI -0.45, 0.26). We found no association between CHD and fetal growth measures in newborns with Down syndrome or 22q11.2 deletion syndrome. Thus, in certain subtypes of CHD, the contribution of genetic factors to prenatal growth impairment may be more important than circulatory disturbances.

Association Between Low Dairy Intake During Pregnancy and Risk of Small-for-Gestational-Age Infants.

Background Inadequate maternal nutrition is regarded as one of the most important indicators of fetal growth. The aim of this study was to analyze the associated risk of having a small for gestational age (SGA) infant according to the mother's dairy intake during the first half of pregnancy. Methods A prospective cohort study was performed using 1175 healthy pregnant women selected from the catchment area of Virgen de las Nieves University Hospital, Granada (Spain). SGA was defined as neonates weighing less than the 10th percentile, adjusted for gestational age. Factors associated with SGA were analyzed using logistic regression models. Population attributable fractions of SGA according to dairy intake were estimated. Results Dairy intake among women who gave birth to SGA infants was 513.9, versus 590.3g/day for women with appropriate size for gestational age infants (P=0.003). An increased intake of dairy products by 100g/day during the first half of pregnancy decreased the risk of having a SGA infant by 11.0%, aOR=0.89 (0.83, 0.96). A dose-response gradient between dairy intake and SGA was observed. Conclusions An inadequate intake of dairy products is associated with a higher risk of SGA. Our results suggest a possible causal relation between dairy intake during pregnancy and the weight of the newborn, although we cannot discard residual confounding. These results should be further supported by properly designed studies.

Congenital Heart Defects and Indices of Fetal Cerebral Growth in a Nationwide Cohort of 924 422 Liveborn Infants.

Neurodevelopmental disorders are the most common and distressful comorbidities associated with congenital heart defects (CHD). Head circumference at birth (HC), a proxy for prenatal cerebral growth, is an established risk factor for neurodevelopmental disorders. In a nationwide cohort, we included all 924 422 liveborn Danish singletons, 1997 to 2011. CHD was present in 5519. The association between CHD and growth indices was analyzed by multivariable linear regression, adjusted for potential confounders. We report mean differences in gestational age-specific z scores in comparison with the general population. CHD was associated with lower HC z scores, -0.10 (95% confidence interval [CI], -0.13 to -0.08). Several CHD subtypes were associated with smaller HC, eg, hypoplastic left heart syndrome, -0.39 (95% CI, -0.58 to -0.21); common arterial trunk, -0.41 (95% CI, -0.74 to -0.09); and major ventricular septal defects, -0.25 (95% CI, -0.35 to -0.15). Other single-ventricle defects, transposition of the great arteries, tetralogy of Fallot, and anomalous pulmonary venous return, were also associated with smaller HC. Transposition of the great arteries was associated with smaller HC relative to birth weight, -0.26 (95% CI, -0.39 to -0.13). Major ventricular septal defects were associated with larger HC relative to birth weight. The results were consistent under various conditions, eg, when siblings of infants with CHD (n=5311) or infants with other major malformations (n=24 974) were used as the reference. Several subtypes of CHD were associated with smaller HC. The associations with major ventricular septal defects, common arterial trunk, and anomalous pulmonary venous return have not previously been described. Only infants with transposition of the great arteries had smaller HC relative to birth weight.

Poor placental traits reduce kid birth weight in young Saanen dams in the first parity

Placental characteristics are the most important indicators of fetal growth and development that influence kid vitality. The aim of this study was to examine the effect of maternal parity on placental characteristics and birth-related traits in Saanen goats. The experiments were conducted on 41 singleton-bearing Saanen does, ranging from 1 to 4 years of age and classified according to first, second, and third parities. Birth weight, placental weight, placental efficiency, and cotyledon density were influenced by parity (P < 0.05). First-parity does had kids with significantly (P < 0.05) lower birth and placental weights than does of other parities, while they had significantly higher (P < 0.05) placental efficiency and cotyledon density. First-parity does had fewer (P < 0.05) large and total cotyledons than third-parity does. Cotyledon dimensions varied among parities (P < 0.05), while average cotyledon surface area and cotyledon efficiency were the lowest in the first-parity does (P < 0.05). The results suggest that younger dams in the first parity may alter placental characteristics and fetal development, resulting in a reduced birth weight from singleton gestations.

Fetal growth restriction and methylation of growth-related genes in the placenta.

To examine the associations between fetal growth restriction (FGR) and DNA methylation of six growth-related genes in human placenta. A total of 181 mother-newborn pairs (80 FGR cases and 101 controls) were enrolled in this case-control study. Placental DNA methylation was measured by bisulfite pyrosequencing. DNA methylation levels of IGF2 and AHRR were positively associated with newborn birth weight and Quetelet's index, while DNA methylation levels of HSD11B2 and WNT2 were negatively associated with those fetal growth indicators. In addition, significantly elevated odds of FGR birth were associated with increasing DNA methylation of HSD11B2 and WNT2, and decreasing DNA methylation of IGF2. Our findings demonstrated that placental DNA methylation levels of IGF2, AHRR, HSD11B2 and WNT2 were associated with measures of fetal growth.

Perfluoroalkyl Acids in Maternal Serum and Indices of Fetal Growth: The Aarhus Birth Cohort.

Background:Previous studies indicated an association between intrauterine exposure to perfluorooctane sulfonate (PFOS) or perfluorooctanoate (PFOA) and lower birth weight. However, these perfluoroalkyl acids (PFAAs) have to some extent been substituted by other compounds on which little is known.Objectives:We investigated the association between specific PFAAs and birth weight, birth length, and head circumference at birth.Methods:We studied 1,507 mothers and their children from the Aarhus Birth Cohort (2008–2013). Nulliparous women were included during pregnancy, and serum levels of 16 PFAAs were measured between 9 and 20 completed gestational weeks (96% within 13 weeks). For compounds with quantifiable values in > 50% of samples (7 compounds), we report the associations with birth weight, birth length, and head circumference at birth determined by multivariable linear regression.Results:Estimated mean birth weights were lower among women with serum perfluorohexane sulfonate, perfluoroheptane sulfonate, and PFOS concentrations above the lowest exposure quartile, but we found no consistent monotonic dose–response patterns. These associations were stronger when the population was restricted to term births (n = 1,426). For PFOS, the birth weight estimates for the highest versus lowest quartile were –50 g (95% CI: –123, 23 g) in all births and –62 g (95% CI: –126, 3 g) in term births. For the other PFAAs, the direction of the associations was inconsistent, and no overall association with birth weight was apparent. No PFAAs were associated with birth length or head circumference at birth.Conclusions:Overall, we did not find strong or consistent associations between PFAAs and birth weight or other indices of fetal growth, though estimated mean birth weights were lower among those with exposures above the lowest quartile for some compounds.Citation:Bach CC, Bech BH, Nohr EA, Olsen J, Matthiesen NB, Bonefeld-Jørgensen EC, Bossi R, Henriksen TB. 2016. Perfluoroalkyl acids in maternal serum and indices of fetal growth: the Aarhus Birth Cohort. Environ Health Perspect 124:848–854; http://dx.doi.org/10.1289/ehp.1510046

Blood Biomarkers of Late Pregnancy Exposure to Trihalomethanes in Drinking Water and Fetal Growth Measures and Gestational Age in a Chinese Cohort.

Background:Previous studies have suggested that elevated exposure to disinfection by-products (DBPs) in drinking water during gestation may result in adverse birth outcomes. However, the findings of these studies remain inconclusive.Objective:The purpose of our study was to examine the association between blood biomarkers of late pregnancy exposure to trihalomethanes (THMs) in drinking water and fetal growth and gestational age.Methods:We recruited 1,184 pregnant women between 2011 and 2013 in Wuhan and Xiaogan City, Hubei, China. Maternal blood THM concentrations, including chloroform (TCM), bromodichloromethane (BDCM), dibromochloromethane (DBCM), and bromoform (TBM), were measured as exposure biomarkers during late pregnancy. We estimated associations with gestational age and fetal growth indicators [birth weight, birth length, and small for gestational age (SGA)].Results:Total THMs (TTHMs; sum of TCM, BDCM, DBCM, and TBM) were associated with lower mean birth weight (–60.9 g; 95% CI: –116.2, –5.6 for the highest vs. lowest tertile; p for trend = 0.03), and BDCM and DBCM exposures were associated with smaller birth length (e.g., –0.20 cm; 95% CI: –0.37, –0.04 for the highest vs. lowest tertile of DBCM; p for trend = 0.02). SGA was increased in association with the second and third tertiles of TTHMs (OR = 2.91; 95% CI: 1.32, 6.42 and OR = 2.25; 95% CI: 1.01, 5.03; p for trend = 0.08).Conclusions:Our results suggested that elevated maternal THM exposure may adversely affect fetal growth.Citation:Cao WC, Zeng Q, Luo Y, Chen HX, Miao DY, Li L, Cheng YH, Li M, Wang F, You L, Wang YX, Yang P, Lu WQ. 2016. Blood biomarkers of late pregnancy exposure to trihalomethanes in drinking water and fetal growth measures and gestational age in a Chinese cohort. Environ Health Perspect 124:536–541; http://dx.doi.org/10.1289/ehp.1409234