[Show abstract][Hide abstract] ABSTRACT: Context: In adult women, Anti-Müllerian hormone (AMH) is produced by small growing follicles, and circulating levels of AMH reflect the number of antral follicles as well as primordial follicles. Whether AMH reflects follicle numbers in healthy girls remains to be elucidated. Objective: To evaluate if serum levels of AMH reflects ovarian morphology in healthy girls. Design: Population-based cohort study. Setting: General community. Participants: 121 healthy girls aged 9.8 - 14.7 years. Main outcome measures: Clinical examination, including pubertal breast stage (Tanner´s classification B1 - 5). Ovarian volume as well as the number and size of antral follicles were assessed by two independent modalities: A) Magnetic resonance imaging (MRI): Ellipsoid volume, follicles ≥ 2mm, and B) Transabdominal ultrasound (TAUS): Ellipsoid- and 3D volume, follicles ≥ 1mm. Circulating levels of AMH, inhibin B, estradiol, FSH and LH were assessed by immunoassays; testosterone and androstenedione by LC-MS/MS. Results: AMH reflected the number of small (MRI 2 - 3mm) and medium (4 - 6mm) follicles (Pearson´s Rho (r) = 0.531 and r = 0.512, p<0.001) but not large follicles (≥ 7mm) (r = 0.109, p=0.323). In multiple regression analysis, small and medium follicles (MRI ≤ 6mm) remained the main contributors to circulating AMH (Beta 0.501, p<0.001) whereas the correlation between AMH and estradiol was negative (Beta -0.318, p=0.005). In early puberty (B1 - B3), the number of AMH-producing follicles (2 - 6mm) correlated positively with pubertal stages (r=0.453, p=0.001), whereas AMH levels were unaffected (-0.183, p=0.118). Conclusions: Similarly to adult women, small and medium antral follicles (≤ 6mm) were the main contributors to circulating levels of AMH in girls.
[Show abstract][Hide abstract] ABSTRACT: Aimational screening programmes for congenital adrenal hyperplasia now include measuring several adrenal metabolites using highly sensitive liquid chromatography-tandem mass spectrometry. The aim of thisstudy was tocompare neonatal hormonal profiles - whole blood concentrations of 17α-hydroxyprogesterone, androstenedione, and cortisol - with genotypes in 21-hydroxylase deficiency.Methods
The study included 62 patients with congenital adrenal hyperplasia born between 1982 and 2012 and 61 random controls born in 1985 and 2005. Patients were grouped according to mutation-based predictions of enzyme impairment. Groups Null and A were salt-wasting (n=35), Group B was simple virilising (n=7) and Group C wasnon-classic(n=20). Dried blood spot samples were retrieved from the Danish Neonatal Screening Biobank.ResultsAll patients with molecular verified 21-hydroxylase deficiency had significantly higher concentrations of 17α-hydroxyprogesterone (p<0.001), androstenedione (p<0.001) anda higher ratio ((17α-hydroxyprogesterone + androstenedione)/cortisol, p<0.05) than controls. Androstenedione showed a higher sensitivity (72%)than 17α-hydroxyprogesterone (12%)to correctly identify Groups B and C.Conclusion
There were significant differences in neonatal hormonal profiles between all groups and controls. This confirms that hormonal disturbances are already detectable in both severe and mild forms of congenital adrenal hyperplasia in neonatal life.This article is protected by copyright. All rights reserved.
[Show abstract][Hide abstract] ABSTRACT: Age at pubertal onset varies substantially in healthy girls. Although genetic factors are responsible for more than half of the phenotypic variation, only a small part has been attributed to specific genetic polymorphisms identified so far. Follicle-stimulating hormone (FSH) stimulates ovarian follicle maturation and estradiol synthesis which is responsible for breast development. We assessed the effect of three polymorphisms influencing FSH action on age at breast deveopment in a population-based cohort of 964 healthy girls. Girls homozygous for FSHR -29AA (reduced FSH receptor expression) entered puberty 7.4 (2.5-12.4) months later than carriers of the common variants FSHR -29GG+GA, p = 0.003. To our knowledge, this is the strongest genetic effect on age at pubertal onset in girls published to date.
[Show abstract][Hide abstract] ABSTRACT: The influence of sex, age, pubertal development and oral contraceptives on dehydroepiandrosterone (DHEA), DHEA sulphate (DHEAS), 17α-hydroxyprogesterone (17-OHP), Δ4-androstenedione (Adione), testosterone (T), calculated free testosterone (fT), free androgen index (FAI) and selected ratios in 1798 serum samples from healthy children, adolescents and young adults was evaluated. Samples were analysed by Turboflow-LC-MS/MS. Sex hormone-binding globulin was analysed by immunoassay. All steroid metabolite concentrations were positively associated with age and pubertal development in both sexes and generally higher in males than in females except for Adione. The pubertal rise in T in males was more pronounced compared to females, reflecting contribution from the testes. Ratios between steroid metabolites varied and depended on sex and age. All ratios were lower during infancy compared to later in life. Use of oral contraceptives significantly lowered serum concentrations of all steroid metabolites, fT, FAI, the 17-OHP/Adione, the Adione/T and the DHEA/Adione ratios, but not the DHEA/DHEAS ratio. We provide reference ranges for DHEA, DHEAS, 17-OHP, Adione, T, fT, FAI and selected ratios in relation to sex, age and pubertal development. Use of oral contraceptives strongly influences adrenal steroidogenesis and should be considered when diagnosing and monitoring treatment of patients with disorders of sex development.
[Show abstract][Hide abstract] ABSTRACT: Although common reproductive problems, such as male infertility and testicular cancer, present in adult life, strong evidence exists that these reproductive disorders might have a fetal origin. The evidence is derived not only from large epidemiological studies that show birth-cohort effects with regard to testicular cancer, levels of testosterone and semen quality, but also from histopathological observations. Many infertile men have histological signs of testicular dysgenesis, including Sertoli-cell-only tubules, immature undifferentiated Sertoli cells, microliths and Leydig cell nodules. The most severe gonadal symptoms occur in patients with disorders of sexual development (DSDs) who have genetic mutations, in whom even sex reversal of individuals with a 46,XY DSD can occur. However, patients with severe DSDs might represent only a small proportion of DSD cases, with milder forms of testicular dysgenesis potentially induced by exposure to environmental and lifestyle factors. Interestingly, maternal smoking during pregnancy has a stronger effect on spermatogenesis than a man's own smoking. Other lifestyle factors such as alcohol consumption and obesity might also have a role. However, increasing indirect evidence exists that exposure to ubiquitous endocrine disrupting chemicals, present at measurable concentrations in individuals, might affect development of human fetal testis. If confirmed, health policies to prevent male reproductive problems should not only target adult men, but also pregnant women and their children.
[Show abstract][Hide abstract] ABSTRACT: Background
Humans are exposed to tributyltin (TBT), previously used as an antifouling paint in ships, mainly through fish consumption. As TBT is a known obesogen, we studied the association of placenta TBT and other organotin compounds (OTCs) with ponderal index (PI) and growth during the first 18 months of life in boys.
In a prospective Finnish study, 110 placenta samples were collected from mothers of boys born in 1997-1999 with (n = 55) and without (n = 55) cryptorchidism. To account for the original study design, linear regression, weighted for sampling fractions of boys with (121/55) and without (5677/55) cryptorchidism from the total cohort, was used to study the association between placenta OTCs and children's weight, length, growth rates and PI up to 18 months of age.
Placenta TBT concentrations were above the limit of quantification (LOQ) in 99% of the samples. However, monobutyltin (MBT), dibutyltin (DBT) and triphenyltin (TPhT) concentrations were below LOQ in 90%, 35% and 57% of samples, respectively. Placenta TBT was positively associated (p = 0.024) with weight gain during the first three months of life, but no other significant associations were observed for weight or length gain. Also, no significant associations between placenta OTC concentrations and child length, weight or PI at any time point were found.
We observed a trend towards higher weight gain from birth to 3 months of age with increasing placenta TBT concentration. These results should be interpreted with caution because obesogenic effects in animal experiments were seen after in-utero TBT exposures to doses that were orders of magnitude higher. Also the number of study subjects included in this study was limited.
Environmental Health 06/2014; 13(45). · 2.71 Impact Factor
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[Show abstract][Hide abstract] ABSTRACT: Some phthalates have shown anti-androgenic effects in rat offspring. Premature infants may be exposed to high amounts of specific phthalates during hospitalization and thus are potentially at risk.
Environmental Health Perspectives 05/2014; · 7.26 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Background: Few human studies have examined bisphenol A (BPA) exposure in relation to semen quality and reproductive hormones in men, and results are divergent.Objectives: We examined associations between urinary BPA concentration and reproductive hormones, as well as semen quality, in young men from the general population.Methods: Our study population consisted of 308 young men from the general population. Urinary BPA concentration was measured by isotope dilution TurboFlow-liquid chromatography-tandem mass spectrometry. We used multiple linear regression analysis to estimate associations between BPA concentration and reproductive hormones and semen quality, adjusting for confounding factors.Results: We found that 98% of the men had detectable urinary levels of BPA. Median (5th-95th percentiles) BPA concentration was 3.25 ng/mL (0.59-14.89 ng/mL). Men with BPA concentrations above the lowest quartile had higher concentrations of serum testosterone, luteinizing hormone (LH), estradiol, and free testosterone compared with the lowest quartile (ptrend ≤ 0.02). Men in the highest quartile of BPA excretion had on average 18% higher total testosterone (95% CI: 8, 28%), 22% higher LH (95% CI: 6, 39%), and 13% higher estradiol (95% CI: 4, 24%) compared with lowest quartile. Men in the highest quartile of BPA also had significantly lower percentage progressive motile spermatozoa compared with men in the lowest quartile (-6.7 percentage points, 95% CI: -11.76, -1.63). BPA was not associated with other semen parameters. Adjusting for dietary patterns did not influence the results.Conclusions: The pattern of associations between BPA and reproductive hormones could indicate an antiandrogenic or antiestrogenic effect, or both, of BPA on the hypothalamic-pituitary-gonadal hormone feedback system, possibly through a competitive inhibition at the receptor level. However, additional research is needed to confirm our findings and to further test the suggested potential mechanisms.Citation: Lassen TH, Frederiksen H, Jensen TK, Petersen JH, Joensen UN, Main KM, Skakkebaek NE, Juul A, Jørgensen N, Andersson AM. 2014. Urinary bisphenol A levels in young men: association with reproductive hormones and semen quality. Environ Health Perspect 122:478-484; http://dx.doi.org/10.1289/ehp.1307309.
Environmental Health Perspectives 05/2014; 122(5):478-484. · 7.26 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Experimental studies have shown that dioxin-like chemicals may interfere with aspects of the endocrine system including growth. However, human background population studies are, however, scarce. We aimed to investigate whether early exposure of healthy infants to dioxin-like chemicals was associated with changes in early childhood growth and serum IGF1. In 418 maternal breast milk samples of Danish children (born 1997-2001) from a longitudinal cohort, we measured polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans, and polychlorinated biphenyls (pg or ng/g lipid) and calculated total toxic equivalent (total TEQ). SDS and SDS changes over time (ΔSDS) were calculated for height, weight, BMI, and skinfold fat percentage at 0, 3, 18, and 36 months of age. Serum IGF1 was measured at 3 months. We adjusted for confounders using multivariate regression analysis. Estimates (in parentheses) correspond to a fivefold increase in total TEQ. TEQ levels in breast milk increased significantly with maternal age and fish consumption and decreased with maternal birth year, parity, and smoking. Total TEQ was associated with lower fat percentage (-0.45 s.d., CI: -0.89; -0.04), non-significantly with lower weight and length at 0 months, accelerated early height growth (increased ΔSDS) (ΔSDS 0-18 months: +0.77 s.d., CI: 0.34; 1.19) and early weight increase (ΔSDS 0-18: +0.52 s.d., CI: 0.03; 1.00), and increased IGF1 serum levels at 3 months (+13.9 ng/ml, CI: 2.3; 25.5). Environmental exposure to dioxin-like chemicals was associated with being skinny at birth and with higher infant levels of circulating IGF1 as well as accelerated early childhood growth (rapid catch-up growth).
[Show abstract][Hide abstract] ABSTRACT: Background/Objectives:Total body fat percentage (%BF) evaluated by dual energy X-ray absorptiometry (DXA) scans (DXA %BF) is widely recognized as a precise measure of fatness. We aimed to establish national reference curves for DXA %BF, %BF calculated from skinfolds (SF %BF) and waist circumference (WC) in healthy children, and to compare agreement between the different methods.Subjects/Methods:Based on 11 481 physical examinations (anthropometry) and 1200 DXA scans from a longitudinal cohort of Danish children (n=2647), we established reference curves (LMS-method) for SF %BF, WC (birth to 14 years) and DXA %BF (8-14 years). Age- and sex-specific Z-scores for body mass index (BMI), WC and SF %BF were compared. Sensitivity and specificity were calculated for agreement of WC, SF %BF and BMI with DXA %BF to identify obese children (>+1 s.d.).Results:%BF differed with age, sex, pubertal stage and social class. SF %BF correlated strongly with DXA %BF (r=0.86). BMI and WC also correlated positively with DXA %BF (Z-scores; r= 0.78 and 0.69). Sensitivity and specificity were 79.5 and 93.8 for SF %BF, 75.9 and 90.3 for BMI and 59.2 and 95.4 for WC.Conclusions:SF %BF showed the highest correlation and best agreement with DXA %BF in identifying children with excess fat (+1 s.d.).European Journal of Clinical Nutrition advance online publication, 29 January 2014; doi:10.1038/ejcn.2013.282.
European journal of clinical nutrition 01/2014; · 3.07 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Adrenal disorders like Congenital Adrenal Hyperplasia result in abnormal adrenal size and morphology, but little is known about the clinical value of magnetic resonance imaging (MRI) in determining adrenal volume.
To evaluate the potential usefulness of MR methodology to estimate adrenal size in healthy children, and to evaluate determinants of adrenal volume such as age, gender, body size, pubic hair stage and serum level of adrenal androgens.
235 healthy children (116 girls) (age range 10.0-14.8 years) were examined by MRI. Clinical examinations (anthropometry and pubertal staging) were performed and five androgen metabolites measured in blood samples by liquid chromatography-tandem mass spectrometry (LC-MS/MS).
It was possible to determine adrenal volume in 115/235 children using MRI. The adrenals were not measurable in 51% of children due to breathing and moving artefacts. The median volume of the right adrenal gland was 0.46 mL in girls and 0.46 mL in boys. The median volume of the left adrenal gland was 0.34 mL in girls and 0.40 mL in boys. Adrenal size was positively associated with body surface area (estimate B=0.34 mL/year, p=0.003), age (estimate B=0.05 mL/year, p=0.021) and pubic hair stage (estimate B=0.05 mL/stage, p=0.075). No associations between adrenal size and serum levels of adrenal androgens were observed.
It was possible to determine adrenal volume by MRI in only 50% of healthy children aged 10-15 years. Adrenal volume increased with age and Tanner stage of pubic hair. Future studies will unravel if adrenal MRI is useful when evaluating children with adrenal diseases. This article is protected by copyright. All rights reserved.
[Show abstract][Hide abstract] ABSTRACT: IntroductionInsulin-like factor 3 (INSL3) is a promising marker of Leydig cell function with potentially high clinical relevance. Limited data of INSL3 levels in relation to other reproductive hormones in healthy pubertal boys exist.AimTo evaluate longitudinal serum changes in INSL3 compared to luteinizing hormone (LH), follicle-stimulating hormone (FSH), testosterone, inhibin B, and anti-Müllerian hormone (AMH) during puberty in healthy boys.Methods
Ten boys were included from the longitudinal part of the COPENHAGEN Puberty Study. Pubertal evaluation, including testicular volume, was performed and blood samples drawn every 6 months for 5 years. Serum concentrations of testosterone were determined by a newly developed LC-MS/MS method, and serum concentrations of INSL3, AMH, inhibin B, FSH and LH, respectively, were determined by validated immunoassays.ResultsSerum INSL3 levels increased progressively with increasing age, pubertal onset and testicular volume. In six of ten boys, LH increased prior to the first observed increase in INSL3. In the remaining four boys, the increase in LH and INSL3 was observed at the same examination. The increases in serum concentrations of LH, testosterone and INSL3 were not parallel or in ordered succession and varied inter-individuallyConclusion
We demonstrated that INSL3 concentrations were tightly associated with pubertal onset and increasing testicular volume. However, the pubertal increases in LH, INSL3, and testosterone concentrations were not entirely parallel, suggesting that INSL3 and testosterone may be regulated differently. Thus, we speculate that INSL3 provides additional information on Leydig cell differentiation and function during puberty compared with traditional markers of testicular function.
[Show abstract][Hide abstract] ABSTRACT: Several non-persistent industrial chemicals have shown endocrine disrupting effects in animal studies and are suspected to be involved in human reproductive disorders. Among the non-persistent chemicals which have been discussed intensively during the past years are phthalates, bisphenol A, triclosan and parabens because of their anti-androgenic and/or estrogenic effects.Phthalates are plastizers used in numerous of industrial products. Bisphenol-A is the main component of polycarbonate plastics and epoxy resins. Parabens and triclosan are anti-microbial preservatives and other phenols such as benzophenone-3 act as UV-screener, while chloro-phenols and phenyl phenols are used as pesticides and fungicides in agriculture.In spite of the widespread use of industrial chemicals, knowledge about exposure sources and human biomonitoring studies among different segments of the population are very limited. In Denmark we have no survey programs for non-persistent environmental chemicals as it is known in some countries like USA (NHANES) and Germany (GerES). However, we have analyzed the excretion of seven parabens, nine phenols and metabolites of eight different phthalates in urine samples collected during the past 6 years from four Danish cohorts. Here we present biomonitoring data in more than 3600 Danish children, adolescents, young men and pregnant women from the general population. Our study shows that nearly all Danes were exposed to the six most common phthalates, to bisphenol A, triclosan and benzophenon-3 and to at least two of the parabens. The exposure to other non-persistent chemicals was also widespread. Our data indicates decreasing excretion of two common phthalates (DnBP and DEHP) over time.
[Show abstract][Hide abstract] ABSTRACT: Many phthalates, parabens and phenols are suspected to have endocrine disrupting properties in humans. They are found in consumer products, including food wrapping, cosmetics and building materials. The foetus is vulnerable and exposure to these chemicals is of particular concern for pregnant women. We therefore studied current exposure to several commonly used phthalates, parabens and phenols in 200 healthy, pregnant Danish women. A total of 200 spot urine samples were collected between weeks 8-30 of pregnancy and analysed for 10 phenols, 7 parabens and 16 phthalate metabolites by LC-MS/MS. The 33 analytes represent 26 non-persistent compounds. The majority of analytes were present in urine from most women. Thus, in 174 of the 200 women, metabolites of more than 13 (>50%) of 26 compounds were detected simultaneously. The number of compounds detected per woman (either as the parent compound or its metabolite (s)) ranged from 7 to 21 with a median of 16. The majority of compounds correlated positively with each other within and between chemical groups suggesting joint exposure sources. Estimated daily intakes (DI) of phthalates and bisphenol A (BPA) were below their individual tolerable daily intake (TDI) and with Hazard Quotients (HQ) below 1. In conclusion, we found detectable levels of phthalate metabolites, parabens and phenols in almost all pregnant women, suggesting combined multiple exposures. Although the individual estimated DI of phthalates and BPA was below TDI, our results still raise concern. As current toxicological risk assessments in humans do not take into account simultaneous exposure, the true cumulative risk for the foetus may be underestimated.
[Show abstract][Hide abstract] ABSTRACT: Geographical differences in occurrence of diseases in male reproductive organs including malformation in reproductive tract have been reported between Denmark and Finland. The reason for these differences is unknown, but differences in exposure to chemicals with endocrine disrupting abilities have been suggested. Among these chemicals are perfluoro¬alkylated substances (PFASs) a group of water and grease repellent chemicals used in outdoor clothes, cookware, food packaging and textiles. We therefore investigated differences in PFASs exposure levels between Denmark and Finland and associated PFASs levels in cord blood with congenital cryptorchidism. Boys from a joint ongoing prospective birth cohort study were included. We analyzed PFASs levels in cord blood serum samples from 29 Danish boys with congenital cryptorchidism; 30 healthy Danish matched controls recruited from 1997-2001, 30 Finnish cases and 78 Finnish healthy matched controls recruited from 1997-1999. Additionally, 48 Finnish cases recruited from 2000-2002 were included. PFOA and PFOS were detected in all 215 Danish and Finnish cord blood samples with significantly higher levels in Danish (medians; PFOA 2.6 ng/mL, PFOS 9.1 ng/mL) compared to Finnish (medians; PFOA: 2.1 ng/mL, PFOS 5.2 ng/mL) samples. We found no associations between cord blood PFOA and PFOS levels and congenital cryptorchidism after adjustment for confounders. Our data indicate that women in Denmark and Finland are generally exposed to PFOA and PFOS but with country differences in exposure levels. We found no statistical significant association between PFOA and PFOS levels in cord blood and congenital cryptorchidism, however, our study was small and larger studies are warranted.
[Show abstract][Hide abstract] ABSTRACT: Background: Prenatal environmental exposures may influence the risk of developing cardiometabolic disease later in life. The HDL-associated anti-oxidative enzyme paraoxonase 1 (PON1) may protect against atherosclerosis and also hydrolyze environmental chemicals, including organophosphate pesticides. A common polymorphism, PON1 Q192R, affects both properties. The aim of this study was to examine if the PON1 Q192R genotype affects cardiometabolic risk factors in school-age children prenatally exposed to pesticides. Methods: Pregnant women working in greenhouses were categorized as high, medium, or not occupationally exposed to pesticides. At age 6 to11 years, their children underwent a standardized physical examination where blood pressure, skin folds, and other anthropometric parameters were measured. Exposure status was unknown to the examiner. PON1-genotype was determined for 141 children (88 pesticide-exposed and 53 unexposed). Non-fasting serum was analyzed for IGF-1, IGFBP3, insulin, and leptin. Results: Exposed children carrying the PON1 R-allele had higher blood pressure, BMI, abdominal circumference, body fat percentage, and serum concentrations of leptin and IGF-1 than did unexposed children. The effects were associated with the prenatal pesticide exposure level. In contrast, children with the PON1 192 QQ genotype showed no significant effect in these outcomes in regard to prenatal pesticide exposure. Conclusion: Our results suggest a gene-environment interaction between prenatal pesticide exposure and the PON1 genotype that affects cardiometabolic risk markers already known to be associated with the PON1 192 R-allele. The results also illustrate that a hypersusceptible subgroup of the population may be more seriously affected, although average effects may not be evident in the entire population.
141st APHA Annual Meeting and Exposition 2013; 11/2013