BACKGROUND: Diversity is a key component of diet quality and health, but no indicator exists for adolescents under the age of 15 years. OBJECTIVE: To establish a dichotomous indicator for population-level assessment of adolescent dietary diversity as a proxy for micronutrient adequacy. METHODS: We used the probability approach to construct mean probability of adequacy (MPA) of 11 micronutrients from 2 days of 24-hour dietary recall data from NHANES, 2007-2018. For each micronutrient, probability of adequacy was calculated using the best linear unbiased predictor of usual intake. Adolescent dietary diversity score (ADDS) was derived with a maximum score of 10 food groups. Generalized linear mixed models were used to examine associations between ADDS and MPA. Receiver operating characteristic analysis was used to establish a cutoff for minimum dietary diversity for adolescents (MDD-A), using an energy-adjusted logistic model with ADDS predicting MPA > 0.6. RESULTS: Probability of adequacy was greater than 80% for all nutrients except vitamin C (42.1%), folate (65.7%), and calcium (23.8%). Population MPA was 79.4%, and nearly 92% of adolescents had an MPA > 0.6. ADDS was positively associated with MPA, and energy was a significant confounder. Area under the curve was > 0.8 on both days with sensitivity and specificity ranging from 0.71-0.80. The MDD-A cutoff was calculated as 5.12 and 5.10 food groups on day 1 and 2, respectively. CONCLUSIONS: In U.S. adolescents, the best cutoff for a dichotomous indicator of dietary diversity as a proxy for micronutrient adequacy is 6 food groups in a given day. Future research could validate MDD-A and its associated cutoff for use across country contexts.

Food consumption, particularly of animal-based products, is considered the most important contributor to persistent endocrine disrupting chemical (EDC) exposure. This study aims to describe the association between maternal diet during pregnancy and exposure to persistent EDCs using dietary pattern analysis. This study is based on subsamples of the Avon Longitudinal Study of Parents and Children (ALSPAC) (N=422) and the Norwegian Mother, Father, and Child Cohort Study (MoBa) (N=276) which uses data from the Medical Birth Registry of Norway (MBRN). Women in both studies completed food frequency questionnaires (FFQs) during pregnancy, from which consumption data were categorized into 38 aggregated food groups. Maternal blood samples were collected during pregnancy and concentrations of perfluoroalkyl substances (PFAS), polychlorinated biphenyls (PCBs), and organochlorine pesticides (OCPs) in serum/plasma were measured. Dietary patterns were identified using reduced rank regression, with blood EDC concentrations as response variables. Within ALSPAC, all patterns (PFAS, PCB, and OCP) were characterized by high consumption of meat, poultry, white fish, and biscuits. In MoBa, high consumption of sausages and burgers (representing processed meats), pasta, and chocolate bars characterized PCB and OCP dietary patterns, while high consumption of cheese characterized the PFAS pattern. Across both cohorts, PFAS patterns were characterized by high consumption of cheese, PCB patterns by high consumption of rice, and OCP patterns by poultry. Dietary patterns explained between 8 and 20% of the variation in serum EDC concentrations, with explained variance being the highest for PCBs in both cohorts. In conclusion, dietary patterns high in animal-based products appear to be associated with persistent EDC concentrations among pregnant women. Diet explains more variation in PCB concentrations than for other persistent EDC classes. © 2021

BACKGROUND: Endocrine disrupting chemical (EDC) exposure is ubiquitous. EDC exposure during critical windows of development may interfere with the body's endocrine system, affecting growth. Previous human studies have examined one EDC at a time in relation to infant growth. By studying mixtures, the human experience can be better approximated. AIMS: We investigated the association of prenatal exposure to persistent EDCs (per- and polyfluoroalkyl substances (PFAS), polychlorinated biphenyls (PCBs), and organochlorine pesticides (OCPs)) as mixtures with postnatal body size among female offspring. SUBJECTS: We used a sub-sample of the Avon Longitudinal Study of Parents and Children (N = 425), based in the United Kingdom. STUDY DESIGN: We quantified 52 EDCs in maternal serum collected during pregnancy. We used Bayesian kernel machine regression with a random intercept to examine the association of prenatal concentrations of EDC mixtures with longitudinal postnatal body size measures for each EDC class separately (PFAS, PCBs, and OCPs) and for all three classes combined. OUTCOME MEASURES: Weight and height measures at 0, 2, 9, and 19 months were obtained by health professionals as part of routine child health surveillance. RESULTS: The mixture representing all three classes combined (31 chemicals) (n = 301) was inversely associated with postnatal body size. Holding all EDCs in the 31-chemical mixture at the 75th percentile compared to the 50th percentile was associated with 0.15 lower weight-for-age z-score (95% credible interval -0.26, -0.03). Weak inverse associations were also seen for height-for-age and body mass index-for-age scores. CONCLUSIONS: These results suggest that prenatal exposure to mixtures of persistent EDCs may affect postnatal body size.

BACKGROUND: Previous studies of endocrine-disrupting chemicals have examined one of these chemicals at a time in association with an outcome; studying mixtures better approximates human experience. We investigated the association of prenatal exposure to mixtures of persistent endocrine disruptors [per- and polyfluoroalkyl substances (PFAS), polychlorinated biphenyls (PCBs), and organochlorine pesticides] with birth size among female offspring in the Avon Longitudinal Study of Parents and Children (ALSPAC), based in the United Kingdom in 1991-1992. METHODS: We quantified concentrations of 52 endocrine-disrupting chemicals in maternal serum collected during pregnancy at median 15 weeks' gestation. Birth weight, crown-to-heel length, and head circumference were measured at birth; ponderal index and small for gestational age were calculated from these. We used repeated holdout weighted quantile sum regression and Bayesian kernel machine regression to examine mixtures in 313 mothers. RESULTS: Using weighted quantile sum regression, all mixtures (each chemical class separately and all three together) were inversely associated with birth weight. A one-unit increase in WQS index (a one-decile increase in chemical concentrations) for all three classes combined was associated with 55 g (β: -55 g, 95% CI: -89, -22 g) lower birth weight. Associations were weaker but still inverse using Bayesian kernel machine regression. Under both methods, PFAS were the most important contributors to the association with birth weight. We also observed inverse associations for crown-to-heel length. CONCLUSIONS: These results are consistent with the hypothesis that prenatal exposure to mixtures of persistent endocrine-disrupting chemicals affects birth size.

Exposure to endocrine disrupting chemicals (EDCs) is ubiquitous. EDC exposure, especially during critical periods of development like the prenatal window, may interfere with the body's endocrine system, which can affect growth and developmental outcomes such as puberty. Most studies have examined one EDC at a time in relation to disease; however, humans are exposed to many EDCs. By studying mixtures, the human experience can be more closely replicated. We investigated the association of prenatal exposure to persistent EDCs (poly- and perfluoroalkyl substances (PFAS), polychlorinated biphenyls (PCBs), and organochlorine pesticides (OCPs)) as mixtures with early menarche among female offspring in a nested case-control study within the Avon Longitudinal Study of Parents and Children (ALSPAC) recruited in the United Kingdom in 1991-1992. Concentrations of 52 EDCs were quantified in maternal serum samples collected during pregnancy. Daughter's age at menarche was ascertained through mailed questionnaires sent annually. We used repeated holdout weighted quantile sum (WQS) regression and Bayesian kernel machine regression (BKMR) to examine the association between prenatal exposure to multiple EDCs and early menarche (<11.5 (n = 218) vs. ≥11.5 years (n = 230)) for each chemical class separately (PFAS, PCBs, and OCPs) and for all three classes combined. Models adjusted for maternal age at menarche, maternal education, parity, pre-pregnancy body mass index, maternal age, prenatal smoking, and gestational week at sample collection. Mixture models showed null associations between prenatal exposure to EDC mixtures and early menarche. Using WQS regression, the odds ratio for early menarche for a one-decile increase in chemical concentrations for all three classes combined was 0.89 (95% CI: 0.76, 1.05); using BKMR, the odds ratio when all exposures were at the 60th percentile compared to the median was 0.98 (95% CI: 0.91, 1.05). Results suggest the overall effect of prenatal exposure to persistent EDC mixtures is not associated with early menarche.

Perfluoroalkyl substances (PFAS) are chemicals used in the manufacture of consumer products. PFAS may act as endocrine disruptors, influencing metabolic pathways and weight-related outcomes. We analyzed associations of maternal serum pregnancy concentrations of PFAS with gestational weight gain (GWG). We used data from 905 women in a subsample of the Avon Longitudinal Study of Parents and Children. Women were routinely weighed in antenatal check-ups; absolute GWG was determined by subtracting the first weight measurement from the last. Linear regression was used to explore associations of maternal PFAS concentrations with absolute GWG, stratified by pre-pregnancy body mass index. Associations of maternal PFAS concentrations with absolute GWG were null. Ten percent higher perfluorooctane sulfonic acid (PFOS) was associated with GWG of -0.03kg (95% CI: -0.11, 0.06) and -0.12kg (95% CI: -0.30, 0.06) among under-/normal weight and overweight/obese mothers, respectively. Overall, findings suggest no association between maternal PFAS concentrations and GWG.

Evidence indicates that in utero environmental exposures could influence reproduction in female offspring. Perfluoroalkyl substances (PFAS) are synthetic, ubiquitous endocrine disrupting chemicals that can cross the placental barrier. Lower levels of anti-Mullerian hormone (AMH), a biomarker of ovarian reserve, are associated with reduced fertility. We investigated the association between in utero PFAS exposure and AMH levels in female adolescents using data from the Avon Longitudinal Study of Parents and Children, a British pregnancy cohort recruited between 1991 and 1992. Maternal serum samples were collected during pregnancy and analyzed for concentrations of commonly found PFAS-perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), perfluorohexane sulfonate (PFHxS), and perfluorononanoic acid (PFNA). AMH levels were measured in serum of female offspring (mean age, 15.4 years) and log-transformed for analyses. We used a sample of 446 mother-daughter dyads for multivariable linear regression analyses, controlling for maternal age at delivery, pre-pregnancy body-mass index, and maternal education. Multiple imputation was utilized to impute missing values of AMH (61.2%) and covariates. Median PFAS concentrations (ng/mL) were as follows: PFOS 19.8 (IQR:15.1, 24.9), PFOA 3.7 (IQR: 2.8, 4.8), PFHxS 1.6 (IQR: 1.2, 2.2), PFNA 0.5 (IQR: 0.4, 0.7). The geometric mean AMH concentration was 3.9ng/mL (95% CI: 3.8, 4.0). After controlling for confounders, mean differences in AMH per one ng/mL higher PFOA, PFOS, PFHxS, and PFNA were 3.6% (95% CI: 1.4%, 8.6%), 0.7% (95% CI: 0.2%, 1.5%), 0.9% (95% CI: 0.4%, 2.2%), and 12.0% (95% CI: 42.8%, 66.8%) respectively. These findings suggest there is no association between in utero PFAS exposure and AMH levels in female adolescents.

Polychlorinated biphenyls (PCBs) are synthetic, organochlorine compounds previously used in industrial processes. Although banned in 1980's across Europe, these chemicals persist in the environment and are associated with adverse health outcomes in children. We investigated the association between in utero concentrations of PCBs and girls' body fatness. Concentrations of various PCB congeners (PCB 118, PCB 138, PCB 153, PCB 170, and PCB 180) were measured in maternal serum samples collected in the early 1990's. Body fatness was measured in the daughters at 9y of age using body mass index (BMI) and dual-energy x-ray absorptiometry (DXA) for percent body fat. Using multivariable linear regression, we explored associations between prenatal PCB congener concentrations and body fatness outcomes. Among 339 mother-daughter dyads, the median and interquartile range (IQR) for PCB congeners ranged between 15.0ngg(-1) (11.0-20.8) for PCB 118 to 64.6ngg(-1) (48.6-86.3) for PCB 153. Among daughters, the median was 27.5% (21.7-34.6) for percent body fat, 39.6% (36.4-43.5) for percent trunk fat, 4.9kgm(-2) (3.5-7.0) for fat mass index and 18.1kgm(-2) (16.3-20.6) for body mass index. Multivariable-adjusted regression analyses showed little or no association between prenatal PCB concentrations with daughters' body fatness measures. Prenatal concentrations of PCB congeners were not strongly associated with measures of body fatness in girls.

Per- and polyfluoroalkyl substances (PFAS) have been widely used in commercial and industrial manufacturing processes since the 1950s. Inverse associations between prenatal exposure to PFAS and birth size have been found in populations around the globe. This study examined the association of prenatal maternal serum concentrations of perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA), perfluorohexane sulfonic acid (PFHxS), and perfluorononanoic acid (PFNA) and birth size in British boys. The study included 457 mother-son dyads participating in the Avon Longitudinal Study of Parents and Children (ALSPAC). Birth weight (g), crown to heel length (cm), and head circumference (cm) were collected at delivery. PFAS were detected in all maternal serum samples during pregnancy (median: 30 weeks gestation (interquartile range: 12-33)). Median concentrations (interquartile range) were 13.8ng/mL (11.0, 17.7), 3.0ng/mL (2.3, 3.8), 1.9ng/mL (1.4, 2.5), and 0.4ng/mL (0.3, 0.5) for PFOS, PFOA, PFHxS, and PFNA, respectively. In multivariable linear regression models, inverse associations were detected between PFOS (continuous) and birth weight (beta=-8.50g, 95% CI=-15.93, -1.07g), crown to heel length (beta=-0.04cm, 95% CI=-0.08, -0.01cm), and head circumference (beta=-0.02cm, 95% CI=-0.04, -0.002cm). In conclusion, prenatal exposure to high levels of PFOS may be associated with reduced birth size in male infants.

BACKGROUND: The developing brain is susceptible to exposure to neurodevelopmental toxicants such as pesticides. AIMS: We explored associations of prenatal serum concentrations of hexachlorobenzene (HCB), beta-Hexachlorocyclohexane (beta-HCH), 2,2-Bis(4-chlorophenyl)-1,1-dichloroethene (p,p'-DDE) and 2,2-Bis(4-chlorophenyl-1,1,1-trichloroethane (p,p'-DDT) with maternal-reported measures of verbal and non-verbal communication in young girls. STUDY DESIGN AND METHODS: We studied a sample of 400 singleton girls and their mothers participating in the Avon Longitudinal Study of Parents and Children (ALSPAC) using multivariable linear regression models adjusting for parity, Home Observation Measurement of the Environment (HOME) score, maternal age and education status, and maternal tobacco use during the first trimester of pregnancy. EXPOSURE AND OUTCOME MEASURES: Maternal serum samples (collected at median 15 wks. gestation [IQR 10, 28]) were assessed for selected organochlorine pesticide levels. Communication was assessed at 15 and 38 months, using adapted versions of the MacArthur Bates Communicative Development Inventories for Infants and Toddlers (MCDI). RESULTS: At 15 months, girls born to mothers with prenatal concentrations of HCB in the highest tertile had vocabulary comprehension and production scores approximately 16% (p = 0.007) lower than girls born to mothers with concentrations in the lowest tertile. This association varied by maternal parity in that the evidence was stronger for daughters of nulliparous mothers. At 38 months, girls born to mothers with prenatal concentrations of HCB in the highest tertile had mean adjusted intelligibility scores that were 3% (p = 0.03) lower than those born to mothers with concentrations in the lowest tertile; however, results did not vary significantly by parity. Maternal concentrations of beta-HCH and p,p'-DDE were not significantly associated with MCDI scores at 15 or 36 months. p,p'-DDT had an inconsistent pattern of association; a significant positive association was observed between p,p'-DDT with verbal comprehension scores at 15 months; however, at 38 months a significant inverse association was observed for p,p'-DDT with communicative scores. This inverse association for p,p'-DDT among older girls tended to be stronger among daughters of mothers who had lower depression scores. CONCLUSIONS: Organochlorine pesticide exposure in utero may affect communication development.

Prenatal exposures to perfluoroalkyl substances (PFAS) have been associated with developmental outcomes in offspring. We found that prenatal concentrations of some PFAS may be associated with reduced bone mass and size in 17-year-old British girls, although it is not clear whether these associations are driven by body size. PURPOSE: PFAS are used to make protective coatings on common household products. Prenatal exposures have been associated with developmental outcomes in offspring. Using data from the Avon Longitudinal Study of Parents and Children (ALSPAC), we investigated the association between prenatal concentrations of PFAS and bone health in girls at 17 years of age and whether body composition can explain any associations. METHODS: We measured concentrations of perfluorooctane sulfonate (PFOS), perfluorooctanoate (PFOA), perfluorohexane sulfonate (PFHxS), and perfluorononanoic acid (PFNA) in maternal serum samples collected during pregnancy. We obtained bone health outcomes in the girls, such as bone mineral density, bone mineral content, bone area, and area-adjusted bone mineral content from whole-body dual-energy X-ray absorptiometry (DXA) scans. We used multivariable linear regression to explore associations between each PFAS and each bone health outcome with adjustment for important confounders such as girls' age at clinic visit, maternal education, and gestational age at sample collection. We also controlled for girls' height and lean mass to explore the role body composition had on observed associations. RESULTS: Prenatal PFOS, PFOA, PFHxS, and PFNA concentrations were associated with inverse effects on bone size and mass after adjusting for important confounders. Conversely, PFNA was positively associated with area-adjusted bone mineral content. However, most significant associations attenuated after additional controlling for height and lean mass. CONCLUSIONS: Prenatal concentrations of some PFAS may be associated with reduced bone mass and size in adolescent girls, although it is not clear whether these associations are driven by body size.

Polychlorinated biphenyls (PCBs) are synthetic chemicals that bioaccumulate in the food chain. PCBs were used primarily for industrial applications due to their insulating and fire retardant properties, but were banned in the 1970s in the United States and in the 1980s in the United Kingdom, as adverse health effects following exposure were identified. Previous studies of populations with high PCB exposure have reported inverse associations with birth weight and gestational length. Birth weight is a powerful predictor of infant survival, and low birth weight can predispose infants to chronic conditions in adult life such as diabetes and cardiovascular diseases. Using data from the Avon Longitudinal Study of Parents and Children, we investigated the association between prenatal exposure to PCBs and fetal growth in a sample of 448 mother-daughter dyads. Concentrations of three common PCB analytes, PCB-118, PCB-153 and PCB-187, were measured in maternal serum collected during pregnancy, and fetal growth was measured by birth weight and birth length. Multivariable linear regression was used to examine the associations between PCB analytes and measures of fetal growth, after adjusting for parity, maternal age, pre-pregnancy BMI, educational status, tobacco use and gestational age of infant at sample collection. Birth length, ponderal index and gestational age were not associated with any of the PCB analytes. Mothers' educational status modified associations for PCB analytes with birthweight. We observed significant inverse associations with birth weight only among daughters of mothers with less education. Daughter's birth weight was -138.4g lower (95% CI: -218.0, -58.9) for each 10ng/g lipid increase in maternal serum PCB-118. Similarly, every 10ng/g lipid increase in maternal serum PCB-153 was associated with a -41.9g (95% CI: -71.6, -12.2) lower birth weight. Every 10ng/g lipids increase in maternal serum PCB-187, was associated with a -170.4g (95% CI: -306.1, -34.7) lower birth weight, among girls with mothers in the lowest education group. Our findings suggest that prenatal exposure to PCBs is inversely associated with daughters' birth weight and that mothers' education, which is a possible marker for socioeconomic status, significantly modified the association between maternal PCB concentrations and birth weight in female newborns.

OBJECTIVE: To evaluate the role of vitamin D intake and serum levels on conception of clinical pregnancy and live birth. DESIGN: Prospective cohort study. SETTING: Academic medical centers. PATIENT(S): Healthy, nulliparous women, age 18-39 years, and their male partners. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Clinical pregnancy and live birth were compared between those who did or did not meet the vitamin D estimated average requirement (EAR) intake (10 mug/d) and with serum 25-hydroxyvitamin D (25(OH)D) considered at risk for inadequacy or deficiency (<50 nmol/L) or sufficient (≥50 nmol/L). RESULT(S): Among 132 women, 37.1% did not meet the vitamin D EAR and 13.9% had serum levels at risk for inadequacy or deficiency. Clinical pregnancies were significantly higher among women who met the vitamin D EAR (67.5% vs. 49.0%) and with sufficient serum 25(OH)D (64.3% vs. 38.9%) compared with those who did not. Live births were higher among those who met the vitamin D EAR (59.0% vs. 40.0%). The adjusted odds ratio (AOR) of conceiving a clinical pregnancy was significantly higher among those who met the EAR (AOR = 2.26; 95% confidence interval [CI], 1.05-4.86) and had sufficient serum 25(OH)D (AOR = 3.37; 95% CI, 1.06-10.70). The associations were not significant after controlling for selected nutrients and dietary quality. CONCLUSION(S): Women with vitamin D intake below EAR and serum 25(OH)D levels at risk for inadequacy or deficiency may be less likely to conceive and might benefit from increased vitamin D intake to achieve adequacy. CLINICAL TRIAL REGISTRATION NUMBER: NCT00642590.

Perfluoroalkyl substances (PFAS), found in many household products and classed as endocrine disrupting chemicals, can be transferred through the placenta and are associated with multiple developmental deficits in offspring. Using data from the Avon Longitudinal Study of Parents and Children (ALSPAC), we investigated the association between intrauterine exposure to PFAS and early communication development in 432 mother-daughter dyads at 15 and 38months of age. Concentrations of perfluorooctane sulfonate (PFOS), perfluorooctanoate (PFOA), perfluorohexane sulfonate (PFHxS), and perfluorononanoate (PFNA) were measured in maternal serum collected during pregnancy. Early communication development was measured with the ALSPAC-adapted MacArthur Communicative Development Inventories for Infants and Toddlers. The infant questionnaire measured verbal comprehension, vocabulary comprehension and production, nonverbal communication, and social development. The toddler questionnaire measured language, intelligibility, and communicative sub-scores. Multivariable linear regression was used to examine associations between each PFAS exposure and each communication sub-scale score. The association between maternal PFAS concentrations and early communication development at 15 and 38months of age varied by maternal age at delivery. In daughters of younger mothers (<25years of age), every 1ng/mL of PFOS was associated with a 3.82 point (95% confidence interval (CI): -6.18, -1.47) lower vocabulary score at 15months and a 0.80 point (95% CI: -1.74, 0.14) lower language score at 38months. Prenatal exposure to select PFAS was positively and negatively associated with communication development among girls, with inconsistent pattern of association across all measured PFAS and endpoints.

Phytoestrogens are estrogenic compounds that occur naturally in plants. Phytoestrogens can cross the placenta, and animal studies have found associations between in utero exposure to phytoestrogens and markers of early puberty. We investigated the association between in utero exposure to phytoestrogens and early menarche (defined as <11.5 years of age at onset) using data from a nested case-control study within the Avon Longitudinal Study of Parents and Children, a longitudinal study involving families living in the South West of England. Concentrations of six phytoestrogens were measured in maternal urine samples collected during pregnancy. Logistic regression was used to explore associations between tertiles of phytoestrogen concentrations and menarche status, with adjustment for maternal age at menarche, maternal education, pre-pregnancy body mass index (BMI), child birth order, duration of breastfeeding, and gestational age at sample collection. Among 367 mother-daughter dyads, maternal median (interquartile range) creatinine-corrected concentrations (in microg/g creatinine) were: genistein 62.1 (27.1-160.9), daidzein 184.8 (88.8-383.7), equol 4.3 (2.8-9.0), O-desmethylangolensin (O-DMA) 13.0 (4.4-34.5), enterodiol 76.1 (39.1-135.8), and enterolactone 911.7 (448.1-1558.0). In analyses comparing those in the highest tertile relative to those in the lowest tertile of in utero phytoestrogen exposure, higher enterodiol levels were inversely associated with early menarche (odds ratio (OR)=0.47; 95% confidence interval (CI): 0.26-0.83), while higher O-DMA levels were associated with early menarche (OR=1.89; 95% CI: 1.04-3.42). These findings suggest that in utero exposure to phytoestrogens may be associated with earlier age at menarche, though the direction of association differs across phytoestrogens.

BACKGROUND: Perfluoroalkyl substances (PFASs) are used in surface coatings that resist stains, grease, and water. METHODS: The association between in utero PFAS exposure and girls' body fatness at age 9 was analyzed in The Avon Longitudinal Study of Parents and Children (UK). Maternal serum [median 15 weeks: interquartile range (IQR) 10 and 28 weeks of gestation] was analyzed for perfluorooctane sulfonate (PFOS), perfluorooctanoate (PFOA), perfluorohexane sulfonate (PFHxS), and perfluorononanoate (PFNA). Body composition was measured by dual X-ray emission absorptiometry, and percent total body fat (%BF) was calculated. Associations between PFASs and body fatness were modeled by multivariable linear regression. RESULTS: Among 359 girls, median (IQR) %BF was 27.5 (IQR 21.7-34.6). Median (IQR) concentrations (all ng/mL) were 3.7 (2.9-4.8) for PFOA, 19.8 (15.0-25.3) for PFOS, 1.6 (1.3-2.2) for PFHxS, and 0.5 (0.4-0.7) for PFNA. Maternal PFAS concentrations were not significantly associated with daughters' total %BF overall. Mothers' educational status modified associations for PFOA and PFOS with %BF (P-interactions: 0.005 and 0.02, respectively). %BF was higher [1.4%; 95% confidence interval (95% CI): 0.3 to 2.5] for each one unit (ng/mL) higher PFOA among girls with mothers in the middle education group, but lower (-0.6%; 95% CI: -1.12 to -0.04) for the corresponding comparison among girls with mothers with the highest education. %BF was lower (-0.2%; 95% CI: -0.3 to -0.1) for each one unit higher PFOS among girls with the most educated mothers. CONCLUSIONS: Prenatal exposure to PFOA and PFOS was associated with girls' %BF within some strata of maternal education status. PFHxS and PFNA were not associated with %BF.

CONTEXT: Low overnight urinary melatonin metabolite concentrations have been associated with increased risk for breast cancer among postmenopausal women. The Postmenopausal Women's Alcohol Study was a controlled feeding study to test the effects of low to moderate alcohol intake on potential risk factors for breast cancer including serum and urinary levels of hormones and other biomarkers. Previously, we observed significant increases in concentrations of serum estrone sulfate and dehydroepiandrosterone sulfate in participants after consumption of 15 or 30 g (one or two drinks) of alcohol per day. OBJECTIVE: In the present analysis, we evaluated the relationship of alcohol consumption with 24-h urinary 6-sulfatoxymelatonin (6-SMT) concentration (micrograms per 24 h). DESIGN AND PARTICIPANTS: Healthy postmenopausal women (n = 51) consumed a controlled diet plus each of three treatments (a nonalcoholic placebo beverage or 15 or 30 g alcohol/d) during three 8-wk periods in random order under conditions of weight maintenance. MEASURES: 6-SMT was measured in 24-h urine samples that were collected at entry into the study (baseline) and at the midpoint (4 wk) and end (8 wk) of each of the three diet periods. RESULTS: Concentration of 6-SMT was not significantly modified by the alcohol treatment after adjustment for body mass index, hours of sleep, daylight hours, and baseline level of 6-SMT. CONCLUSIONS: These results suggest that low to moderate daily alcohol consumption does not significantly affect 24-h urinary levels of melatonin among healthy postmenopausal women.