Maternal phthalate exposure during pregnancy and testis function of young adult sons.

BACKGROUND: Phthalate exposure during fetal life may disrupt testicular development. Congruent with this, studies have found shorter anogenital distance, reduced penile size and altered hormone levels in infant boys whose mothers were exposed to higher levels of some phthalates during pregnancy. Few studies have explored if such adverse effects persist in adulthood. Thus, we aimed to explore if there is an association between fetal phthalate exposure and markers of testicular function in young adult men. METHODS: In a longitudinal mother-child cohort from Copenhagen, Denmark, we examined 100 young men whose mothers during pregnancy had serum drawn and analyzed for 34 phthalate metabolites. Examinations of the young men took place at 18-20 years of age and included measurements of adult markers of testicular function (reproductive hormones, penile size, anogenital distance (AGD), testis volume, semen quality) and growth factors. Associations between maternal serum concentrations of phthalate metabolites and reproductive measures in the young men were tested using multiple linear regression. RESULTS: Most consistently, higher maternal phthalate exposure was associated with higher luteinizing hormone (LH) but unchanged testosterone in adult sons. Congruently, higher maternal exposure was associated with lower total and free testosterone/LH ratios in adult sons. For example, twice as high maternal MiNP was associated with a 7.9 % (95 % CI 1.6-13.8) lower free testosterone/LH ratio. There was no consistent pattern of associations between the different phthalate metabolites and other reproductive hormones, clinical outcomes, or semen quality. None of the tested associations was significant after multiplicity adjustment. CONCLUSIONS: In this exploratory study, higher maternal exposure to some phthalates was associated with impaired testicular Leydig cell function evidenced by a lower total and free testosterone/LH ratio in adult sons. This unique 18-20-year follow-up study raises concern and suggests that exposure of pregnant women to phthalates may have long-term effects on adult reproductive health in male offspring.

Tracking and Cumulative Lifetime Exposure to IGF-I in 6459 Healthy Individuals and in SGA Children Treated With GH.

CONTEXT: Supraphysiological serum insulin-like growth factor-I (IGF-I) concentrations have been a matter of concern in children treated with GH because high IGF-I levels were associated with risk of later disease in former epidemiological studies. OBJECTIVE: To determine whether a single IGF-I measurement reliably reflects lifetime IGF-I exposure we evaluated intraindividual longitudinal tracking of IGF-I and IGF-binding protein-3 (IGFBP-3) levels and we estimated cumulative lifetime exposure to IGF-I in healthy and GH-treated individuals. METHODS: We included 6459 healthy participants (cross-sectional = 5326; longitudinal = 1133) aged 0-76 years (9963 serum samples) and 9 patients born small-for-gestational-age (SGA) with 238 serum samples during GH treatment. Intraindividual tracking of IGF-I and IGFBP-3 (SD score [SDS]) was determined by intraclass correlation coefficients (ICCs). Cumulative lifetime IGF-I exposure was estimated by area under the curve of the predicted SDS trajectory from 0 to 76 years. RESULTS: For IGF-I (SDS), ICCs were 0.50 (95% CI, 0.47-0.53) for male and 0.53 (0.50-0.56) for female participants. Lifetime IGF-I exposure was significantly higher in female (mean 12 723 ± 3691 SD) than in male participants (12 563 ± 3393); P = 0.02. In SGA children, treatment with GH increased the lifetime exposure to IGF-I from 9512 ± 1889 to 11 271 ± 1689, corresponding to an increase in lifetime IGF-I trajectory from -0.89 SD ± 0.57 to -0.35 SD ± 0.49. CONCLUSION: Because IGF-I and IGFBP-3 levels track throughout life, a single measurement reliably reflects lifetime exposure. GH therapy increased the lifetime exposure to IGF-I only slightly and it remained below the average lifetime exposure in the reference population.

Associations between exposure to perfluoroalkyl substances and body fat evaluated by DXA and MRI in 109 adolescent boys.

BACKGROUND: Exposure to perfluoroalkyl substances (PFASs) has been associated with changes in body mass index and adiposity, but evidence is inconsistent as study design, population age, follow-up periods and exposure levels vary between studies. We investigated associations between PFAS exposure and body fat in a cross-sectional study of healthy boys. METHODS: In 109 boys (10-14 years old), magnetic resonance imaging and dual-energy X-ray absorptiometry were performed to evaluate abdominal, visceral fat, total body, android, gynoid, android/gynoid ratio, and total fat percentage standard deviation score. Serum was analysed for perfluorooctanoic acid, perfluorooctane sulfonic acid (PFOS), perfluorohexane sulfonic acid, perfluorononanoic acid, and perfluorodecanoic acid using liquid chromatography and triple quadrupole mass spectrometry. Data were analysed by multivariate linear regression. RESULTS: Serum concentrations of PFASs were low. Generally, no clear associations between PFAS exposure and body fat measures were found; however, PFOS was negatively associated with abdominal fat (ß = -0.18, P = 0.046), android fat (ß = -0.34, P = 0.022), android/gynoid ratio (ß = -0.21, P = 0.004), as well as total body fat (ß = -0.21, P = 0.079) when adjusting for Tanner stage. CONCLUSIONS: Overall, we found no consistent associations between PFAS exposure and body fat. This could be due to our cross-sectional study design. Furthermore, we assessed PFAS exposure in adolescence and not in utero, which is considered a more vulnerable time window of exposure.

Menstrual Pattern, Reproductive Hormones, and Transabdominal 3D Ultrasound in 317 Adolescent Girls.

CONTEXT: The knowledge of normal variation of reproductive hormones, internal genitalia imaging, and the prevalence of gynecological disorders in adolescent girls is limited. OBJECTIVE: The study aimed to describe reproductive parameters in postmenarchal girls from the general population including the frequency of oligomenorrhea, polycystic ovary syndrome, and use of hormonal contraception. DESIGN: The Copenhagen Mother-Child Cohort is a population-based longitudinal birth cohort of 1210 girls born between 1997 and 2002. SETTING: University hospital. PARTICIPANTS: A total of 317 girls were included, with a median age of 16.1 years and time since menarche of 2.9 years. MAIN OUTCOME MEASURE(S): Tanner stage, height, weight, age at menarche, menstrual cycle length and regularity, ovarian/uterine volume, and number of follicles were recorded. Serum concentrations of FSH, LH, anti-Müllerian hormone (AMH), inhibin B, estradiol, testosterone, SHBG, androstenedione, dehydroepiandrosterone sulfate, 17-OH-progesterone, and IGF-1 were measured. RESULTS: Twenty girls (6.3%) had oligomenorrhea and differed significantly in serum androgens and AMH, age at and time since menarche from girls with regular cycles. Twenty-seven girls were classified with PCOS (8.5%) and had significantly higher 17-OH-progesterone, estradiol, AMH, LH, and age at menarche than the reference group. Girls on oral contraception had significantly higher serum SHBG concentrations and lower serum concentrations of all hormones except AMH and IGF-1. Ovarian follicles 2 to 29.9 mm correlated positively with serum AMH (P < 0.0001). CONCLUSIONS: Most 16-year-old girls had regular menstrual cycles, normal reproductive hormones, and uterine and ovarian ultrasound. Serum AMH reflected ovarian follicle count and may be a useful biomarker of ovarian reserve.

Genetic Variations in FSH Action Affect Sex Hormone Levels and Breast Tissue Size in Infant Girls: A Pilot Study.

CONTEXT: Single nucleotide polymorphisms altering FSH action (FSHB -211G>T, FSHR -29G>A, and FSHR 2039A>G) are associated with peripubertal and adult levels of reproductive hormones and age at pubertal onset in girls. OBJECTIVE: To investigate whether genetic polymorphisms altering FSH action affect serum levels of female reproductive hormones and breast development as early as during minipuberty. DESIGN: Longitudinal study. SETTING: Population-based cohort study. PARTICIPANTS: A total of 402 healthy girls at 3 months of age. MAIN OUTCOME MEASURES: Analyses of single nucleotide polymorphisms by PCR using Kompetitive Allele Specific PCR genotyping assays; identification of glandular breast tissue by palpation and measurement of the diameter. Serum levels of anti-Müllerian hormone, FSH, LH, estradiol, inhibin B, and sex hormone-binding globulin were assessed by immunoassays. RESULTS: FSHR -29G>A was associated with both FSH and anti-Müllerian hormone levels with an A allele effect size of -0.8 IU/L (P = .005) and 1.4 nmol/L (P = .003), respectively. FSHR 2039A>G correlated with breast tissue size with a negative additive effect of minor alleles (P = .021), whereas the effect on estradiol levels was only present in homozygotes. FSHB -211T carriers had smaller breast tissue size than girls who without a minor allele; GT+TT 10.5 (confidence interval 9.4-11.5) mm vs GG 12.1 (confidence interval 11.4-12.8) mm, P = .014. CONCLUSIONS: Our study indicates that 3 genetic polymorphisms altering FSH action, especially FSHR -29G>A and FSHR 2039A>G, affect female hormone profile and glandular breast tissue development already during minipuberty. Thus, genetic variations of FSH signaling appear to determine the individual set point of the hypothalamic-pituitary-gonadal axis already early in life.