Search

Summary Objective SCN1A encodes the alpha subunit of the voltage-gated sodium channel and plays a crucial role in several epilepsy syndromes. The common SCN1A splice-site polymorphism rs3812718 (IVS5N+5 G>A) might contribute to the pathophysiology underlying genetic generalized epilepsies and is associated with electrophysiologic properties of the channel and the effect of sodium-channel blocking antiepileptic drugs. We assessed the effects of the rs3812718 genotype on cortical excitability at baseline and after administration of carbamazepine in order to investigate the mechanism of this association. Methods Paired-pulse transcranial magnetic stimulation (TMS) was applied in 92 healthy volunteers with the homozygous genotypes AA or GG of rs3812718 at baseline and after application of 400 mg of carbamazepine or placebo in a double-blind, randomized, crossover design. Resting motor threshold (RMT), short interval intracortical inhibition (SICI), intracortical facilitation (ICF), and cortical silent period (CSP) were determined. Results At baseline there was no significant difference in any TMS parameter. Genotype GG was associated with a higher carbamazepine-induced increase in CSP duration as compared to AA (multivariate analysis of covariance [MANCOVA], p = 0.013). An expected significant increase in RMT was genotype independent. Significance We found that the rs3812718 genotype modifies the effect of carbamazepine on CSP duration (mainly reflecting modulation of γ-aminobutyric acid (GABA)ergic inhibition), but not on RMT (mainly reflecting modulation of voltage-gated sodium channels). This provides evidence that rs3812718 affects the pharmacoresponse to carbamazepine via an effect on GABAergic cortical interneurons. Our results also confirm that TMS is useful to investigate the effect of genetic variants on cortical excitability and pharmacoresponse.

Study question Does prenatal exposure to perfluoroalkyl substances (PFASs) have long-term effects on female reproductive function?. Summary answer Our results suggest an association between in utero exposure to perfluorooctanoic acid (PFOA) and delay in age of menarche. What is known already Previous cross-sectional studies have reported possible effects of PFASs on female reproduction including reduced fecundity, delayed puberty and accelerated age at menopause. Only limited data exist from follow-up studies on long-term implications of prenatal exposure to PFASs. Study design, size, duration In this study we used data from a Danish population-based cohort established in 1988-1989. Of 1212 eligible pregnant women, 965 participated. Follow-up was initiated in 2008 on the female offspring at ∼20 years of age. Three hundred and sixty seven (84%) daughters answered a questionnaire and 267 (61%) daughters furthermore attended clinical examinations which were conducted in 2008-2009. Participants/materials, setting, methods The final study population consisted of 343 daughters of which 254 had attended the clinical examinations and 89 had answered the questionnaire only. Levels of PFASs in maternal serum from pregnancy week 30 were used as a measure of prenatal exposure and related to age of menarche, menstrual cycle length, levels of reproductive hormones and follicle number of the daughters. Data were divided into three groups according to tertiles of maternal concentrations of PFASs (low, medium, high). Main results and the role of chance In adjusted regression analyses, daughters exposed to higher levels of PFOA in utero had a 5.3 (95% confidence interval: 1.3; 9.3) months later age of menarche compared with the reference group of lower PFOA. Crude (P = 0.05) and adjusted (P = 0.01) trend tests also indicated a relationship between higher prenatal PFOA exposure and delay of menarche. Limitations, reasons for caution We did not measure the exact amount of PFASs to which the daughters had been exposed prenatally. Instead we used PFAS concentrations in maternal serum as surrogates. However, PFASs are efficiently transferred to the fetus via placenta. Information on age of menarche was collected retrospectively but the time interval for recall in our study was relatively short (2-10 years). The remaining outcome measures depended on participation in clinical examination which reduced the number of observations leading to limited statistical power and risk of selection bias. Wider implications of the findings Since PFASs can be detected in humans all over the world, effects of prenatal exposure on female reproductive function later in life may have wide health implications. Study funding/competing interest(s) The study was supported by the Danish Council for Independent Research (271-05-0296, 09-065631), the Danish Ministry of Interior and Health (0-302-02-18/5), the Danish Council for Strategic Research (09-067124 (Centre for Fetal Programming), 09-063072, 2101-06-0005), the Novo Nordisk Foundation, the Aarhus University Research Foundation, the Frimodt-Heineke Foundation, the Foundation of Maria Dorthea and Holger From, the Beckett-Foundation, the Research Grant of Organon and the Foundation of Lily Benthine Lund. There are no competing interests. Trial registration number Not applicable.

Background: Perfluorinated alkyl acids (PFAAs), persistent chemicals with unique water-, dirt-, and oil-repellent properties, are suspected of having endocrine-disrupting activity. The PFAA compounds perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) are found globally in humans; because they readily cross the placental barrier, in utero exposure may be a cause for concern. Objectives: We investigated whether in utero exposure to PFOA and PFOS affects semen quality, testicular volume, and reproductive hormone levels. Methods: We recruited 169 male offspring (19–21 years of age) from a pregnancy cohort established in Aarhus, Denmark, in 1988–1989, corresponding to 37.6% of the eligible sons. Each man provided a semen sample and a blood sample. Semen samples were analyzed for sperm concentration, total sperm count, motility, and morphology, and blood samples were used to measure reproductive hormones. As a proxy for in utero exposure, PFOA and PFOS were measured in maternal blood samples from pregnancy week 30. Results: Multivariable linear regression analysis suggested that in utero exposure to PFOA was associated with lower adjusted sperm concentration (ptrend = 0.01) and total sperm count (ptrend = 0.001) and with higher adjusted levels of luteinizing hormone (ptrend = 0.03) and follicle-stimulating hormone (ptrend = 0.01). PFOS did not appear to be associated with any of the outcomes assessed, before or after adjustment. Conclusions: The results suggest that in utero exposure to PFOA may affect adult human male semen quality and reproductive hormone levels.

Background: The biopersistent organochlorine pollutants dichlorodiphenyldichloroethylene (p,p′-DDE), hexachlorobenzene (HCB) and polychlorinated biphenyls (PCBs) can be detected in humans worldwide. The chemicals can cross the placenta and may interfere with endogenous hormonal homeostasis. Objectives: To investigate effects on female reproduction following intrauterine exposure to selected biopersistent organochlorines. Methods: We used data from a Danish pregnancy cohort with follow-up on 436 eligible daughters at approximately 20 years of age. Information on age of menarche (n = 335), menstrual cycle length (n = 230) and serum concentrations of reproductive hormones (n = 243) was obtained. Number of antral follicles was counted by vaginal ultrasound (n = 147). Of 244 daughters who attended clinical examination, 170 used hormonal contraceptives and 74 were non-users. Concentrations of p,p′-DDE, HCB and six PCB congeners were analysed in maternal serum samples obtained in pregnancy week 30. Results: Age of menarche and menstrual cycle length were found not to be statistically significant associated with prenatal organochlorine exposure. Among non-users of hormonal contraceptives with information on antral follicle number (n = 43), daughters exposed to the highest tertile of p,p′-DDE had 28% (95% confidence interval (95% CI): 5; 46%) lower follicle number compared to the low-level exposed reference group. Those exposed to medium and higher levels of HCB had 30% (95% CI: 5; 48%) and 28% (95% CI: 7; 44%) lower follicle number compared to the reference group. Furthermore, maternal serum HCB concentrations were inversely associated with free androgen index among non-users of hormonal contraceptives (n = 73). These associations were not found in users of hormonal contraceptives. Conclusions: Among non-users of hormonal contraceptives, we found indications of adverse long-term effects on female reproduction following prenatal exposure to biopersistent organochlorines. These findings may have wide implications for public health as intrauterine exposure occurs worldwide. Keywords: Persistent organochlorines, Female reproduction, Ovary, Fetal development, Epidemiology

Persistent organochlorine pollutants (POPs) are ubiquitous, bioaccumulative compounds with potential endocrine-disrupting effects. They cross the placental barrier thereby resulting inin uteroexposure of the developing fetus. The objective of this study was to investigate whether maternal serum concentrations of polychlorinated biphenyls (PCBs) andp,p′-dichlorodiphenyldichloroethylene (p,p′-DDE) during pregnancy are associated with son's semen quality and reproductive hormone levels. During 2008–2009, we recruited 176 male offspring from a Danish cohort of pregnant women who participated in a study in 1988–1989. Each provided semen and blood samples that were analyzed for sperm concentration, total sperm count, motility, and morphology, and reproductive hormone levels, respectively. The maternal blood samples were collected in pregnancy week 30 and were analyzed for the concentrations of six PCBs (PCB-118, -138, -153, -156, -170, and -180) andp,p′-DDE. The potential associations betweenin uteroexposure to ΣPCBs (pmol/ml), Σdioxin like-(DL) PCBs (PCB-118 and -156) (pmol/ml), andp,p′-DDE and semen quality and reproductive hormone levels were investigated using multiple regression. Maternal median (range) exposure levels of ΣPCB, ΣDL-PCB, andp,p′-DDE were 10.0 (2.1–35.0) pmol/ml, 0.8 (0.2–2.7) pmol/ml, and 8.0 (0.7–55.3) pmol/ml, respectively, reflecting typical background exposure levels in the late 1980s in Denmark. Results suggested thatin uteroexposure to ΣPCB, ΣDL-PCB, andp,p′-DDE was not statistically significantly associated with semen quality measures or reproductive hormone levels. Thus, results based on maternal PCB andp,p′-DDE concentrations alone are not indicative of long-term consequences for male reproductive health; however, we cannot exclude that these POPs in concert with other endocrine-modulating compounds may have adverse effects.

During the last decades there has been an increasing awareness of pollution in tunnel wash water and highway runoff, and its ecotoxicological effects. The objectives of the present thesis were to investigate trace element accumulation and the levels of the biomarkers metallothionein (MT), 7-Ethoxyresorufin O-deethylase (EROD), glutathione S-transferase (GST) and reduced glutathione (GSH) in common frog (Rana temporaria) embryos and tadpoles inhabiting Vassum and Skullerud sedimentation ponds along E6 in southeast Norway. A naturally occurring rainwater pond was also included in the study. Tadpoles and water samples were collected weekly in May and June 2012 and analyzed for 34 elements, including several metals of environmental concern. The chemical analyses detected total chromium (Cr), copper (Cu) and zinc (Zn) concentrations in the two sedimentation ponds high enough for the water quality to be classified as ‘poor’ or ‘very poor’ at several samplings, according to the classification system developed by the Climate and Pollution Agency. However, the highest concentrations of the majority of the trace elements were identified in the naturally occurring rainwater pond, probably due to impact from an abandoned shooting range nearby. For practically all of the rest of the elements the highest concentrations were detected in Vassum, while more moderate concentrations of most elements were measured in Skullerud. Frog embryos and tadpoles in all three ponds showed a significant time dependent trace element accumulation. The statistics were performed using the first principal component site scores derived from a principal component analysis (PCA) on tadpole tissue element concentrations as representative values for overall element accumulation (henceforth referred to simply as ‘overall tissue element concentrations’). The overall tissue element concentrations reached the highest levels in Vassum tadpoles although the highest total and dissolved water concentrations of most elements were detected in the naturally occurring pond. No significant correlation was found between trace element concentrations in water and tadpoles, respectively. The levels of MT, EROD, GST and GSH varied significantly with time in tadpoles in all three ponds. Overall tissue element concentrations could not explain the variation in MT, EROD or GSH as no significant correlation was found between overall tissue element concentrations and these biomarkers. However, significant positive correlation was found between MT and tissue lead (Pb) concentrations when testing this separately. Significant positive correlation was also found between overall tissue element concentrations and GST, and between GST and tissue cadmium (Cd) concentrations, and GST and tissue Pb concentrations when testing this separately. Hence, the results suggest that overall tissue element concentrations, as well as tissue Cd and Pb concentrations, can possibly explain some of the variation in GST. Altogether, the lack of an adequate reference group makes it difficult to conclude whether any of the biomarkers are induced above basal level. The results suggest that R. temporaria tadpoles growing up in the sedimentation ponds as well as the naturally occurring pond may be adversely affected by contaminants in the water. Controlled exposure studies or field studies including a proper reference group are needed to identify the basal level of biomarkers in tadpoles and demonstrate any departures from the natural variation. Statens vegvesen, Vegdirektoratet

STUDY QUESTION: Does in utero exposure to constituents of cigarette smoke have a programming effect on daughters' age of menarche and markers of long-term reproductive health? SUMMARY ANSWER: In utero exposure to constituents of cigarette smoke was associated with earlier age of menarche and--to a lesser extent--changes in the testosterone profile of the young women. WHAT IS KNOWN ALREADY: Studies observe potential effects of in utero exposure to constituents of cigarette smoke on the intrauterine formation of female gonads, but the consequences on long-term reproductive health in daughters remain unclear. STUDY DESIGN, SIZE AND DURATION: A prospective cohort study was designed using data from 965 pregnant women enrolled prior to a routine 30th-week antenatal examination at a midwifery practice in Denmark from 1988 to 1989 and a follow-up of their 19-21-year-old daughters in 2008. PARTICIPANTS/MATERIALS, SETTING AND METHODS: The pregnant women provided information on lifestyle factors during pregnancy, including the exact number of cigarettes smoked per day during the first and the second trimesters. A total of 438 eligible daughters were asked to complete a web-based questionnaire on reproductive health and subsequently invited to participate in a clinical examination during 2008. Of the 367 daughters (84%) who answered the questionnaire, 267 (61%) agreed to further examination. Information on menstrual pattern was provided at examination, blood samples were drawn to be analyzed for serum levels of reproductive hormones [FSH, LH, estradiol (E(2)), sex hormone-binding globulin, anti-Müllerian hormone, dehydroepiandrosterone-sulphate (DHEAS), free testosterone and free E(2)] and number of follicles (2-9 mm) were examined by transvaginal ultrasound. The daughters were divided into three exposure groups according to the level of maternal smoking during first trimester [non-exposed (reference), low-exposed (mother smoking >0-9 cigarettes/day) and high-exposed (mother smoking ≥ 10 cigarettes/day)]. Data were analyzed by multiple regression analyses in which we adjusted for potential confounders. Both crude and adjusted test for trend were carried out using maternal smoking during the first trimester as a continuous variable. MAIN RESULTS AND THE ROLE OF CHANCE: We observed an inverse association between in utero exposure to constituents of cigarette smoke and age of menarche (P = 0.001). Daughters exposed to >0-9 cigarettes/day debuted with -2.7 [95% confidence interval (CI) -5.2 to -0.1] percentage earlier age of menarche, whereas daughters exposed to ≥ 10 cigarettes/day had -4.1 (95% CI: -6.6 to -1.5) percentage earlier age of menarche corresponding to 6.5 (95% CI: -10.7 to -2.2) months. There was a non-significant tendency towards lower levels of testosterone and DHEAS with increasing in utero exposure to constituents of cigarette smoke but no associations with follicle number, cycle length or serum levels of the other reproductive hormones were observed. LIMITATIONS AND REASONS FOR CAUTION: We collected information on age of menarche retrospectively but the recall time was relatively short (2-10 years) and the reported values were within the normal range of Caucasians. Analyses of reproductive hormones are presented only for the group of daughters who were non-users of hormonal contraceptives because users were excluded, leaving only a low number of daughters available for the analyses (n = 75), as reflected in the wide CIs. The analyses of hormones were further adjusted for menstrual phase at time of clinical examination (follicular, ovulation and luteal phase) because blood samples were not collected on a specific day of the menstrual cycle. WIDER IMPLICATIONS OF THE FINDINGS: This study supports the limited evidence of an inverse association between maternal smoking during pregnancy and age of menarche and further addresses to what extent reproductive capacity and hormones may be programmed by maternal smoking during pregnancy. A trend toward earlier maturation of females is suggested to have implications on long-term reproductive function. STUDY FUNDING/COMPETING INTEREST(S): Supported by a scholarship from The Lundbeck Foundation (R93-A8476). No conflict of interest declared.

Objective To investigate the association between serum antimullerian hormone (AMH) and other reproductive parameters in young women. Design Cross-sectional study. Setting University hospital. Patient(s) Population-based cohort of 256 women: 180 were users and 76 were nonusers of hormonal contraceptives. Intervention(s) None. Main Outcome Measure(s) Antral follicles, androgens, age at menarche, and duration and regularity of menstrual cycle. Result(s) AMH levels were lower among users of hormonal contraceptives compared to nonusers. Among nonusers, women with AMH levels in the upper tertile had 55% (95% confidence interval [CI]: 22%–99%) higher levels of total T and 8% (95% CI=2%–15%) longer menstrual cycles than women with AMH levels in the lower tertile. An increase of 1 ng/mL in AMH was associated with 45% (95% CI=6%–97%) higher prevalence of irregular menstrual cycles. These associations were not seen among users of hormonal contraceptives. A strong relationship between AMH and follicle number was found in both users and nonusers. Conclusion(s) AMH measurements were found to be applicable in evaluation of the reproductive function of young women. However, there may be differences in the way that serum AMH levels can be interpreted depending on whether the woman uses hormonal contraceptives or not.

The aim of the present study was to compare assessments of sperm concentration and sperm motility analysed by conventional semen analysis with those obtained by computer-assisted semen analysis (CASA) (Copenhagen Rigshospitalet Image House Sperm Motility Analysis System (CRISMAS) 4.6 software) using semen samples from 166 young Danish men. The CRISMAS software identifies sperm concentration and classifies spermatozoa into three motility categories. To enable comparison of the two methods, the four motility stages obtained by conventional semen analysis were, based on their velocity classifications, divided into three stages, comparable to the three CRISMAS motility categories: rapidly progressive (A), slowly progressive (B) and non-progressive (C+D). Differences between the two methods were large for all investigated parameters (P

background: According to the Rotterdam 2003 criteria, an ovary is defined as polycystic if 12 or more follicles of 2 –9 mm are present, when evaluating the ovary by ultrasonography on Days 3 –5 of the menstrual cycle in women not using hormonal contraceptives. The aim of this population-based study was to estimate the prevalence of polycystic ovaries (PCO) in a representative sample of young Danish women according to the Rotterdam criteria. methods: From a Danish pregnancy cohort established in 1988–1989, 267 (61%) young adult daughters agreed to participate in a clinical examination and 174 (40%) consented to vaginal ultrasound. Sufficient image quality in at least one ovary was obtained from 154 women. Both users and non-users of hormonal contraceptives were included and the examination was not restricted to a particular time of the menstrual cycle. results: The median (range) age was 20.1 (19.5 –21.0) years. The median follicle number per ovary was 14 (6 –30) and 12 or more follicles were counted in 104 of the 154 women. Thus, the prevalence was estimated to 68% [95% confidence interval (CI): 60– 74%]. PCO were present in 80% (95% CI: 65– 89%) of non-users (n ¼ 44) of hormonal contraceptives. Of the 104 women with PCO, 41% (95% CI: 32–51%) could be defined as having polycystic ovary syndrome. conclusions: A very large proportion of the young women had PCO according to the Rotterdam 2003 criteria. As the number of follicles is higher at a younger age, we believe the Rotterdam criteria should be revised, particularly to avoid misdiagnosis in this age group.