Search

• A novel, specific, and sensitive isotope diluted LC-MS/MS method was developed for simultaneous quantitation of 16 steroid hormone metabolites. • Steroid metabolites in serum from healthy infants, children, adolescents, and adults aged 0.17 months to 77 years (n = 2458) were analysed. • Sex- and age specific reference intervals of 15 steroid metabolites were established. Reference intervals covering the whole life span for all the metabolites in the steroid hormone biosynthesis quantified by sensitive and robust analytical methods are sparse or not existing. To develop a state-of-the-art LC-MS/MS method for simultaneous quantification of multiple steroid metabolites and to establish detailed sex- and age-specific reference intervals for 16 steroid metabolites. An isotope diluted LC-MS/MS method was developed for simultaneous quantitation of 16 steroid hormones. Serum samples from cross-sectional cohorts of healthy infants, children, adolescents, and adults aged 0.17 months to 77 years (n = 2458) were analysed. With this novel, specific, and sensitive LC-MS/MS method, it was possible to quantify progesterone, 17-hydroxypregnenolone, 17-hydroxyprogesterone, dehydroepiandrosterone sulfate, androstenedione, testosterone, dihydrotestosterone, 11-deoxycorticosterone, corticosterone, 11-deoxycortisol, cortisol, and cortisone in ≥90 % of the samples, while estrone sulfate, aldosterone and dehydroepiandrosterone were quantified in 77 %, 75 % and 60 % of the samples, respectively. 21-deoxycortisol was only detectable in 2.5 % of samples from healthy subjects. Sex- and age-dependent fluctuations observed in minipuberty, puberty and adulthood including the menopausal transition were modelled. This enabled us to establish valid reference intervals from birth to late adult life for both males and females. Detailed sex- and age-specific reference intervals of multiple, simultaneously quantified steroid metabolites by a novel and specific LC-MS/MS method provides a valuable tool for clinical practice and for future research. [ABSTRACT FROM AUTHOR]

Sperm concentration is an essential parameter in the diagnostic evaluation of men from infertile couples. It is usually determined by manual counting using a hemocytometer, and is therefore both laborious and subjective. We have earlier shown that a newly developed image cytometry (IC) method may be used to determine sperm concentration. Here we present a validation of the IC method by analysis of 4010 semen samples. There was high agreement between IC and manual counting at sperm concentrations above 3 mill/ml and in samples with concentrations above 12 mill/ml the two methods can be used interchangeable. However, we found substantial differences in samples below 3 mill/ml. We also assessed the accuracy of the two methods by repeated measurements of 248 samples, which revealed that IC measurements seemed more accurate. Moreover, based on ten samples counted by several operators the IC method had a lower coefficient of variation than the manual method (5% vs 10%), indicating a better precision of the IC method. In conclusion, measurement of sperm concentration by IC can be used at concentrations above 3 mill/ml and seems more accurate and precise than manual counting, making it an attractive option in the daily clinical practice. [ABSTRACT FROM AUTHOR]

Objectives: This study tested whether genetic variation in the CETP gene is consistent with a protective effect of cholesteryl ester transfer protein (CETP) inhibition on risk of ischemic events and on total mortality, without the adverse effects reported for torcetrapib. Background: Torcetrapib, an inhibitor of CETP, increased risk of death and ischemic cardiovascular disease of those randomized to the drug, despite improving the lipid profile. Methods: The Copenhagen City Heart Study is a prospective cohort study of 10,261 individuals, aged 20 to 93 years, who were followed for up to 34 years (1976 to 2010). Of these, 2,087 developed ischemic heart disease, 1,064 developed ischemic cerebrovascular disease, and 3,807 died during follow-up. We selected 2 common genetic variants in CETP previously associated with reductions in CETP activity, thus mimicking the effect of pharmacological CETP inhibition. Results: In individuals carrying 4 versus 0 high-density lipoprotein cholesterol–increasing alleles, there was an increase in levels of high-density lipoprotein cholesterol of up to 14% (0.2 mmol/l), and concomitant decreases in triglycerides, low-density lipoprotein cholesterol, and non–high-density lipoprotein cholesterol of, respectively, 6% (0.1 mmol/l), 3% (0.1 mmol/l), and 4% (0.2 mmol/l) (p for trend 0.004 to <0.001). Corresponding hazard ratios were 0.76 (95% confidence interval [CI]: 0.68 to 0.85) for any ischemic vascular event, 0.74 (95% CI: 0.65 to 0.85) for ischemic heart disease, 0.65 (95% CI: 0.54 to 0.79) for myocardial infarction, 0.77 (95% CI: 0.65 to 0.93) for ischemic cerebrovascular disease, 0.71 (95% CI: 0.58 to 0.88) for ischemic stroke, and 0.88 (95% CI: 0.80 to 0.97) for total mortality. CETP genotypes did not associate with variation in markers of possible side effects previously reported for torcetrapib. Conclusions: Genetic CETP inhibition associates with reductions in risk of ischemic heart disease, myocardial infarction, ischemic cerebrovascular disease, and ischemic stroke, with a corresponding antiatherogenic lipid profile, and with increased longevity, without adverse effects. [Copyright &y& Elsevier]

Background: Development of the gonads during fetal life is complex and vital for adult reproductive health. Cell and animal studies have shown an alarming effect of mild analgesics on germ cells in both males and females. More than 50% of pregnant women use mild analgesics during pregnancy, which potentially could compromise the reproductive health of the next generation. Objectives: We present a research protocol designed to evaluate the effect of prenatal exposure to mild analgesics and endocrine‐disrupting chemicals on gonadal function in the offspring. Population: Healthy, singleton pregnant women and their partners. Design: The COPANA cohort is a prospective, observational pregnancy and birth cohort. Methods: Participants were enrolled during the first trimester of pregnancy. Information on the use of mild analgesics was collected retrospectively 3 months prior to pregnancy and prospectively every 2 weeks throughout the study. We collected extensive data on lifestyle and reproductive health. Biospecimens were collected in the first trimester (maternal and paternal urine‐ and blood samples), in the third trimester in conjunction with a study‐specific ultrasound scan (maternal urine sample), and approximately 3 months post‐partum during the infant minipuberty period (maternal and infant urine‐ and blood samples). A comprehensive evaluation of reproductive function in the infants during the minipuberty phase was performed, including an ultrasound scan of the testis or ovaries and uterus. Preliminary Results: In total, 685 pregnant women and their partners were included between March 2020 and January 2022. A total of 589 infants (287 males) and their parents completed the follow‐up during the minipuberty phase (December 2020—November 2022). Conclusions: The Copenhagen Analgesic Study holds the potential to provide novel and comprehensive insights into the impact of early and late prenatal exposure to mild analgesics and other endocrine‐disrupting chemicals on future reproductive function in the offspring. [ABSTRACT FROM AUTHOR]

Background: Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) may affect the male reproductive system as it uses angiotensin‐converting enzyme (ACE)2, which is expressed in testicular tissue, as an entry point into the cell. Few studies have evaluated the long‐term effects of mild coronavirus disease 2019 (COVID‐19) on testicular function, and insulin‐like factor 3 (INSL3) levels have not previously been assessed during acute SARS‐CoV‐2 infection. Objectives: The aim of the study was to assess the impact of acute SARS‐CoV‐2 infection on testicular function including INSL3 and the presence of SARS‐CoV‐2 RNA in semen in non‐hospitalised men with mild COVID‐19. Materials and methods: This longitudinal study included 36 non‐hospitalised SARS‐CoV‐2‐positive men (median age 29 years). Inclusion was within seven days following a positive SARS‐CoV‐2 reverse‐transcription polymerase chain reaction test. Reproductive hormone levels, semen parameters, and the presence of SARS‐CoV‐2 RNA in oropharyngeal and semen samples were assessed during acute SARS‐CoV‐2 infection (baseline) and at three‐ and six‐month follow‐up. Wilcoxon matched‐pair signed‐rank (two samples) test was used to assess time‐related alterations in reproductive hormone levels and semen parameters. Results: Lower plasma testosterone (T) (total and calculated free (c‐fT)) and higher luteinising hormone (LH) concentrations were observed during acute SARS‐CoV‐2 infection (baseline) compared to three‐ and six‐month follow‐up. Consequently, ratios of c‐fT/LH were lower at baseline compared to three‐ and six‐month follow‐up (p < 0.001 and p = 0.003, respectively). Concomitantly, lower INSL3 concentrations were observed at baseline compared to three‐month follow‐up (p = 0.01). The total number of motile spermatozoa was also lower at baseline compared to six‐month follow‐up (p = 0.02). The alterations were detected irrespective of whether the men had experienced SARS‐CoV‐2‐related fever episodes or not. No SARS‐CoV‐2 RNA was detected in semen at any time point. Discussion and conclusion: This study showed a reduction in testicular function, which was for the first time confirmed by INSL3, in men mildly affected by SARS‐CoV‐2 infection. The risk of transmission of SARS‐CoV‐2 RNA via semen seems to be low. Febrile episodes may impact testicular function, but a direct effect of SARS‐CoV‐2 cannot be excluded. [ABSTRACT FROM AUTHOR]

Clinical proteomics aims to deliver cost-effective multiplexing of potentially hundreds of diagnostic proteins, including distinct protein isoforms. The analytical strategy known as targeted proteomics is particularly promising because it is compatible with robust mass spectrometry (MS)-platforms already implemented in many clinical laboratories for routine quantitation of small molecules (i.e. uHPLC coupled to triple-quadrupole MS). Progress in targeted proteomics of circulating insulin-like growth factor 1 (IGF-I) have provided valuable insights about tryptic peptides, transitions, internal standards and calibrants. The present challenge is to examine if targeted proteomics of IGF-I can truly measure up to the routine performance that must be expected from a clinical testing platform. [ABSTRACT FROM AUTHOR]

An isotope-dilution TurboFlow-LC-MS/MS method for simultaneous quantification of the ten steroid metabolites dehydroepiandrosterone sulfate (DHEAS), progesterone, 17α-hydroxyprogesterone (17-OHP), Δ4-androstenedione (Adione), corticosterone, 11-deoxycortisol, cortisol, cortisone, testosterone (T), and estrone 3-sulfate (E1-S) in serum was developed and validated. Limits of quantification, variability (inter- and intra-day), analytical range and linearity were all found to be acceptable for clinical use. Furthermore, sample stability was evaluated including the influence of freeze-thaw cycles and the effects of temperature and storage time. The method was applied to 391 serum samples from healthy, Danish boys 10–18 years old. The concentration ranges of the included steroid metabolites for this population are presented. Concentrations of DHEAS, 17-OHP, Adione and T in the 391 serum samples were furthermore compared to results obtained using an existing LC-MS/MS method in our laboratory. Excellent agreement was found between the methods. Furthermore, the improved sensitivity of the new method allowed for quantification of a number of samples found to be below the LOQs of the existing method. Thus, the two instruments and their associated methods were validated as possible back-ups for each other, which we consider an extremely important issue in high-throughput laboratories analyzing clinical samples on a regular basis. The ten analytes included can be analyzed simultaneously but it is also possible only to include some of these analytes for specific diagnostic purposes which make the new method an extremely useful tool in the clinical laboratory. [ABSTRACT FROM AUTHOR]

Objective: Little is known about the ratio between luteinizing hormone (L H) and follicle-stimulating hormone (FSH) during infancy. This study aimed to evaluate serum and urinary LH/FSH as a marker of sex with age-specific cutoffs in healthy infants. Design: A prospective, longitudinal cohort study of healthy infants ag ed 0-1.2 years. Methods: In total, 236 healthy infants (122 boys and 114 girls) from The COPENHAGEN Minipuberty Study (ClinicalTrials. gov ID: NCT02784184), with 567 serum and 603 urine samples, wer e included. Measures of diagnostic accuracy, including sensitivity and specificity, were used to assess the a bility of LH/FSH to detect sex in healthy infants. Results: In both serum and urine, LH/FSH was highest in males with mini mal overlap between the sexes. In contrast to isolated LH and FSH concentrations, LH/FSH ratios in both serum and urine were excellent markers of sex from 0 to 1.2 years with median sensitivities and specificities ranging fr om 93 to 100% with correspondingly narrow 95% CIs. Conclusions: Serum and urinary LH/FSH ratios are excellent discriminators of sex in healthy infants during the entire first year of life. The clinical role and application of the rat io remain to be elucidated. [ABSTRACT FROM AUTHOR]

Background: Accurate and selective assessment of testosterone requires use of a sensitive LC-MS/MS method, especially at low levels as those seen in young children. Methods: The present longitudinal study of 20 healthy children from the Copenhagen Puberty Study followed every 6 months for 5 years evaluates the longitudinal increase in serum testosterone before, during and after pubertal onset quantified by a newly developed LC-MS/MS method in comparison with immunoassay. Testosterone concentrations in serum samples (n = 177) were determined by LC-MS/MS (detection limit 0.1 nmol/l) and by immunoassay (detection limit 0.23 nmol/l). Results: Serum concentrations of testosterone increased gradually with age by both methods. However, serum testosterone was quantifiable in 9/10 girls prior to pubic hair development measured with LC-MS/MS, and in 2/10 girls measured with immunoassay. In boys, testosterone was quantifiable in 10/10 boys 1 year prior to pubic hair development measured with LC-MS/MS, and only in 1/10 boys measured with immunoassay. Serum testosterone levels were quantifiable 1.5 years (range 0.5-2.5) earlier using LC-MS/MS. Conclusion: Assessment of longitudinal circulating levels of serum testosterone using a selective LC-MS/MS method proved to be more sensitive in predicting early peripubertal changes in healthy children compared to levels determined by immunoassay. © 2014 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Introduction Fibroblast Growth Factor 21 (FGF21) is a novel metabolic factor with effect on glucose and lipid metabolism, and shown to be elevated in diseases related to metabolic syndrome. Due to the increasing frequency of metabolic syndrome in the pediatric population, and as FGF21 studies in children are limited, we investigated baseline serum levels of FGF21 in healthy children during an oral glucose tolerance test. Methods A total of 179 children and adolescents from the COPENHAGEN Puberty Study were included. An OGTT with glucose and insulin measurements, a dual energy X-ray absorptiometry (DXA) scan and a clinical examination including pubertal staging were done on all subjects. Serum levels of FGF21, adiponectin, and leptin were determined by immunoassays at baseline. Results The girls had significantly higher levels of FGF21 compared with boys (155 pg/mL vs. 105 pg/mL, P = 0.04). 38 children (21%) had levels below detection limit of assay. Baseline levels of FGF21 showed positive correlation with triglycerides, but no significant correlations were found between FGF21-concentration and body mass index (BMI), DXA-derived fat percentage, LDL- HDL- and non-HDL cholesterol, leptin or adiponectin levels, respectively. Neither was any correlation found between baseline FGF21-levels and the dynamic changes in glucose and insulin levels during the OGTT. Conclusion FGF21 is independent of adiposity in children, and the significant metabolic effect seems to be limited to pathological conditions associated with insulin resistance. The higher levels of triglycerides in the girls may explain the significantly higher levels of FGF21 in girls compared with boys. [ABSTRACT FROM AUTHOR]

Using measurements of circulating anti-Müllerian hormone (AMH) in diagnosing and managing reproductive disorders in pediatric patients requires thorough knowledge on normative values according to age and gender.We provide age- and sex-specific reference ranges for the Immunotech assay and conversion factors for theDSL andGeneration II assays.With this tool in hand, the pediatrician can use serum concentrations of AMH when determining the presence of testicular tissue in patients with bilaterally absent testes or more severe Disorders of Sex Development (DSD). Furthermore, AMH can be used as a marker of premature ovarian insufficiency (POI) in both Turner Syndrome patients and in girls with cancer after treatment with alkylating gonadotoxic agents. Lastly, its usefulness has been proposed in the diagnosis of polycystic ovarian syndrome (PCOS) and ovarian granulosa cell tumors and in the evaluation of patients with hypogonadotropic hypogonadism. [ABSTRACT FROM AUTHOR]

Objective To describe the natural history of phenotype, growth and gonadal function in patients with partial androgen insensitivity syndrome. Setting Tertiary paediatric endocrine centre. Methods Retrospective evaluation of 14 male patients with partial androgen insensitivity syndrome (PAIS) with verified androgen receptor (AR) mutations. The authors recorded phenotypic characteristics at birth and external masculinisation score (EMS), registered longitudinal growth, circulating levels of testosterone, estradiol, luteinising hormone (LH), follicle-stimulating hormone (FSH), inhibin-B and sex hormone binding globulin (SHBG), in addition to phenotype at postpubertal follow up. Results The EMS ranged from 5 to 12 in PAIS at birth. Six patients were born with hypospadias and all patients developed gynaecomastia in puberty. Eight of the patients received testosterone treatment. At follow-up penile size was impaired irrespective of EMS at birth, but responded to pubertal androgen therapy in some of the patients. Serum levels of testosterone, estradiol, SHBG and LH, but not FSH and inhibin B, were markedly elevated in puberty. Final height was 181.3 cm (165.7- 190.5 cm) corresponding to an SD score of 0.7 (-2.1 to +2.1 SD, n=10). Conclusion Gynaecomastia and impaired phallic growth are frequently observed in adults with PAIS, but may be ameliorated by androgen therapy. The authors suggest that male patients presenting with gynaecomastia in puberty, and elevated circulating levels of testosterone, estradiol and LH in puberty, but normal FSH, should be suspected of having PAIS and undergo genetic testing for AR mutations. [ABSTRACT FROM AUTHOR]

Background: The hypothalamic‐pituitary‐gonadal (HPG) axis governs sexual maturation and reproductive function in humans. In early postnatal life, it is transiently active during which circulating sex steroids reach adult levels. While this so‐called minipuberty represents a universal phenomenon in infants of both sexes, its role for early maturation and growth remains incompletely understood. Objectives: To provide normative data on auxology as well as serum and urinary hormone levels in healthy, full‐term infants throughout the first year of life and to investigate associations of postnatal HPG axis dynamics as well as hormonal, genetic and environmental exposures with early genital development and growth. Population: Healthy, Danish, full‐term, singleton newborns including their parents. Design: Single‐centre, prospective, observational longitudinal pregnancy and birth cohort. Methods: Newborns were followed with six repeated clinical examinations during a one‐year follow‐up period. An umbilical cord blood sample was drawn at birth. At each visit, infants underwent a clinical examination focusing on auxology and genital development. Further, blood (serum, plasma, DNA) and urine samples were collected at each visit. Mothers and fathers underwent a clinical examination and provided blood samples prior to and after birth. A subset of parents provided urine samples and breast milk samples. Pregnancy and obstetrical outcomes, and detailed parental questionnaires were compiled. Preliminary results: Between August 2016 and August 2018, 2481 women with singleton pregnancies were invited to participate of which 298, including their partners, were enrolled (12.0%). A total of 268 healthy, full‐term newborns born appropriate for gestational age (AGA) were included at birth, 233 newborns participated in the postnatal follow‐up period and 186 completed the one‐year follow‐up period (9.4% and 7.5%, respectively). Conclusion: The COPENHAGEN Minipuberty Study provides detailed, longitudinal data on early genital development and growth including hormonal and genetic profiles and environmental exposure in healthy infants including additional data in their parents. [ABSTRACT FROM AUTHOR]

Background: With the development of molecular high-throughput assays (i.e. next generation sequencing), the knowledge on the contribution of genetic and epigenetic alterations to the etiology of inherited endocrine disorders has massively expanded. However, the rapid implementation of these new molecular tools in the diagnostic settings makes the interpretation of diagnostic data increasingly complex.Main Body: This joint paper of the ENDO-ERN members aims to overview chances, challenges, limitations and relevance of comprehensive genetic diagnostic testing in rare endocrine conditions in order to achieve an early molecular diagnosis. This early diagnosis of a genetically based endocrine disorder contributes to a precise management and helps the patients and their families in their self-determined planning of life. Furthermore, the identification of a causative (epi)genetic alteration allows an accurate prognosis of recurrence risks for family planning as the basis of genetic counselling. Asymptomatic carriers of pathogenic variants can be identified, and prenatal testing might be offered, where appropriate.Conclusions: The decision on genetic testing in the diagnostic workup of endocrine disorders should be based on their appropriateness to reliably detect the disease-causing and -modifying mutation, their informational value, and cost-effectiveness. The future assessment of data from different omic approaches should be embedded in interdisciplinary discussions using all available clinical and molecular data. [ABSTRACT FROM AUTHOR]

Self-reported psychological stress has been associated with decreased semen quality. Cortisol levels in scalp hair (hair cortisol concentration, HCC) has emerged as a potential objective marker of psychological stress. Thus, we investigated if HCC was associated with markers of testicular function. Furthermore, we examined whether three common single nucleotide polymorphisms in the glucocorticoid-receptor gene (NR3C1 , chromosome 5), potentially affecting receptor sensitivity, were associated with HCC and could influence the studied association between HCC and testicular function. Cross-sectional study. We analysed HCC, serum-levels of reproductive hormones, semen parameters, and the three NR3C1- polymorphisms; Bcl I (rs41423247), Tth111 I (rs10052957), and 9β (rs6198), in a population of 696 men from the general population. HCC was not associated with testicular function, and adjustment for the three NR3C1- polymorphisms did not alter the results. However, HCC increased significantly with the number of Tth111 I minor-alleles (T) and decreased significantly with the number of 9β minor-alleles (G). Given previously shown associations between stress and semen quality, and that no association between HCC and self-reported stress was observed in the current study, we speculate that negative reproductive effects of stress may not be mediated directly by cortisol. This study demonstrates associations between HCC and glucocorticoid receptor gene variants indicating that these SNPs may influence systemic glucocorticoid levels, but the potential health effects of such alterations are yet unknown. • Psychological stress has been shown to be associated with impaired semen quality. • Hair cortisol, a potential stress marker, was not associated with testis function. • Adjustment for the Bcl I, Tth111 I, and 9β NR3C1 SNPs did not influence the results. • The Tth111 I and the 9β SNPs were associated with hair cortisol. [ABSTRACT FROM AUTHOR]

Adrenarche is characterized by steadily rising levels of adrenal androgen metabolites from 4–6 years of age. We recently described marked gender-specific differences in circulating ratios between selected adrenal androgen metabolites in a cross-sectional study. This may suggest gender differences in steroidogenic enzyme activities. We therefore aimed at verifying these findings in a prospective, longitudinal study of healthy boys and girls who were examined during pubertal transition. A longitudinal study of 20 healthy children from the COPENHAGEN Puberty Study, followed every 6 months for 5 years. Clinical examinations were conducted and serum concentrations of Androstenedione (Adione), 17-hydroxyprogesterone (17-OHP), testosterone (T), dehydroepiandrosterone (DHEA) and DHEA sulfate (DHEAS) were quantified by a newly developed LC-MS/MS method. DHEA, DHEAS, Adione, 17-OHP and T increase with age. Boys had higher levels of DHEAS from 10.5 years of age, whereas girls had higher levels of Adione from 13 years of age compared to boys. Interestingly, we observed significantly higher ratios of DHEAS/DHEA (sulfotransferase activity) in boys before and after pubertal onset compared to girls, whereas Adione/17-OHP (CYP 17 activity) appeared to increase more in pubertal girls compared to boys. This suggests that adrenal steroidogenic enzyme activities show developmental as well as gender-specific changes in healthy children. [ABSTRACT FROM AUTHOR]

The influence of sex, age, pubertal development and oral contraceptives on dehydroepiandrosterone (DHEA), DHEA sulfate (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 analyzed by Turboflow-LC–MS/MS. Sex hormone-binding globulin was analyzed 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. [ABSTRACT FROM AUTHOR]

Parabens are added to personal care products as antimicrobial preservatives. They have been suggested to have endocrine disrupting abilities. Prenatal exposure to parabens has been associated with reproductive endpoints including reduced male anogenital distance (AGD, distance from anus to genitals), which is sensitive to prenatal anti-androgenic exposure. To study the associations between maternal paraben concentrations in second trimester urine and AGD and reproductive hormone concentrations at 3 months of age in offspring. Pregnant women from Odense, Denmark were included in early pregnancy from 2010 to 12, and their children are being followed up. Fasting spot urine samples from 536 pregnant women were analyzed for methylparaben (MeP), ethyl-paraben (EtP), iso-propylparaben (i-PrP), n-propylparaben (n-PrP), n-butylparaben (n-BuP) and benzylparaben (BzP) by liquid chromatography tandem mass spectrometry and thereafter osmolarity adjusted. Three months after expected date of birth, AGD was measured in 452 children, and serum concentrations of follicle stimulating hormone (FSH), luteinizing (LH), testosterone, dehydroepiandrosterone-sulphate (DHEAS), androstenedione and 17-hydroxyprogesterone (17-OHP) were measured in 198 children. Maternal paraben exposure was categorized into tertiles or below and above level of detection, and sex-stratified multiple linear regression analyses were performed with AGD or reproductive hormones as outcomes. Most pregnant women had low concentrations of parabens in urine, but 10% exceeded the threshold for adverse estrogenic effects. Higher maternal paraben exposure was associated with shorter AGD in male offspring and longer AGD in girls, although only significant for MeP in boys. In addition, FSH, LH, DHEAS, 17-OHP concentrations were lower in girls with high prenatal paraben exposure, whereas no consistent pattern was found in boys. The endocrine disrupting abilities of parabens may affect humans at vulnerable time periods during development, which may have long term impact on reproductive function. This is the first study to find these associations in girls and our findings need confirmation. Unlabelled Image • Parabens are antimicrobial preservatives and suggested to have endocrine disrupting abilities. • Among 536 Danish pregnant women paraben in urine were low, but 10.4% exceeded the threshold for adverse estrogenic effects. • Higher maternal paraben exposure was associated with shorter anogenital distance (AGD) in boys and longer AGD in girls. • Sex hormone concentrations were lower in girls with high prenatal paraben exposure. • Prabens may affect humans at vulnerable time periods during development. [ABSTRACT FROM AUTHOR]