Hair cortisol, glucocorticoid gene receptor polymorphisms, stress, and testicular function.

Objective: 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.

FSHB and FSHR gene variants exert mild modulatory effect on reproductive hormone levels and testis size but not on semen quality: A study of 2020 men from the general Danish population.

Background: Spermatogenesis depends on stimulation by follicle-stimulating hormone (FSH) which binds to FSH receptors (FSHR) on testicular Sertoli cells. Three FSH-related single-nucleotide polymorphisms (SNPs), FSHB -211G>T (rs10835638), FSHR -29G>A (rs1394205) and FSHR 2039A>G (rs6166) affect FSH action, and have been suggested to affect testicular function, but the evidence is uncertain.

Objective: To describe the associations between the three SNPs and testicular function in a large and well-characterised cohort of men from the general population.

Impact of psychological stress measured in three different scales on testis function: A cross-sectional study of 1362 young men.

Background: Studies have reported associations between psychological stress and semen quality, but most have been performed on selected populations using different stress measures. Thus, it is uncertain which stress scale best quantifies the effects of stress on testicular function.

Objective: To study the association between three different measures of stress and testicular function in young men.

Testicular microlithiasis on scrotal ultrasound in 4850 young men from the general population: associations with semen quality.

Background: Testicular microlithiasis (TM) is sometimes found on scrotal ultrasound. The prevalence seems higher in populations of men with testicular dysfunction, and TM may be a risk factor for testicular germ cell neoplasia in situ in men with additional risk factors. The association between TM and testicular function is controversial, especially in incidentally found TM.

Evaluation of Serum Insulin-like Factor 3 Quantification by LC-MS/MS as a Biomarker of Leydig Cell Function.

Background: The peptide hormone insulin-like factor 3 (INSL3) is a marker for Leydig cell function and the clinical use of serum INSL3 measurements has been suggested by several groups.

Aim: (1) To establish a reference range for liquid chromatography-tandem mass spectrometry (LC-MS/MS) of serum INSL3 in healthy boys and men; and (2) to compare the associations of serum INSL3 and testosterone (T) to pubertal stage, lifestyle factors, diurnal variation, body composition, and human chorionic gonadotropin (hCG) stimulation.

Results: In a reference range based on LC-MS/MS analysis of serum from 1073 boys and men, INSL3 increased from levels close to the detection limit (0.

Psychological stress, stressful life events, male factor infertility, and testicular function: a cross-sectional study.

Objective: To assess the association between psychological stress and male factor infertility as well as testicular function (semen quality, serum reproductive hormones) and erectile dysfunction.

Design: Cross-sectional study.

Setting: University Hospital-based research center.

Development and validation of a mass spectrometry-based assay for quantification of insulin-like factor 3 in human serum.

Background: The circulating level of the peptide hormone insulin-like factor 3 (INSL3) is a promising diagnostic marker reflecting Leydig cell function in the male. Few commercial immunoassays of varying quality exist. Therefore, we decided to develop and validate a precise method for quantification of INSL3 by mass spectrometry.

Polymorphisms in JMJD1C are associated with pubertal onset in boys and reproductive function in men.

JMJD1C, a member of the Jumonji-domain containing histone demethylases protein family, has been associated with levels of sex-hormone binding globulin (SHBG) and testosterone in men, and knock-out rodent models show age-dependent infertility. The objective of this study was to investigate whether single nucleotide polymorphisms (SNPs) nearby JMJD1C are associated with pubertal onset in boys and with male reproduction. 671 peri-pubertal boys, 1,027 young men, 315 fertile men, and 252 infertile men were genotyped for two JMJD1C SNPs (rs7910927 and rs10822184).

Anti-Müllerian hormone levels and fecundability in women with a natural conception.

Objectives: To investigate the association between anti-Müllerian hormone (AMH), a well-established marker of the ovarian reserve, and time-to-pregnancy (TTP) in natural conceptions, and to assess changes in serum-AMH in early pregnancy.

Study Design: A cross sectional study comprising 279 women aged 21-42 years with a natural conception recruited during 2012-2014. AMH was measured in gestational week 10-19.

Gynaecomastia in 786 adult men: clinical and biochemical findings.

Objective: Gynaecomastia is a benign proliferation of glandular tissue of the breast; however, it is an important clinical observation because it can be the first symptom of an underlying disease. Some controversy exists concerning the clinical importance of an in-depth investigation of men who develop gynaecomastia. We hypothesise that a thorough work-up is required in adult men with gynaecomastia.

Dynamic GnRH and hCG testing: establishment of new diagnostic reference levels.

Objective: Gonadotropin-releasing hormone (GnRH) and human chorionic gonadotropin (hCG) stimulation tests may be used to evaluate the pituitary and testicular capacity. Our aim was to evaluate changes in follicular-stimulating hormone (FSH), luteinizing hormone (LH) and testosterone after GnRH and hCG stimulation in healthy men and assess the impact of six single nucleotide polymorphisms on the responses.

Design: GnRH and hCG stimulation tests were performed on 77 healthy men, 18-40 years (reference group) at a specialized andrology referral center at a university hospital.

Is Sedentary Lifestyle Associated With Testicular Function? A Cross-Sectional Study of 1,210 Men.

Based on cross-sectional data on 1,210 healthy young Danish men, we investigated whether sedentary lifestyle was associated with testicular function (semen quality and reproductive hormones) independent of physical activity. The men were invited to participate in the study between 2008 and 2012, when they attended a compulsory medical examination to determine their fitness for military service. Information on sedentary behavior (television watching and computer time) and physical activity was obtained by questionnaire.

Vitamin D deficiency and low ionized calcium are linked with semen quality and sex steroid levels in infertile men.

Study Question: Are low vitamin D levels linked with semen quality and sex steroids in infertile men?

Summary Answer: Infertile men with vitamin D deficiency had lower sperm motility, total numbers of motile sperm, Inhibin B, sex-hormone-binding-globulin (SHBG) and testosterone/estradiol ratio, but higher levels of free sex steroids, than infertile men with normal vitamin D levels.

What Is Known Already: Low vitamin D levels have been associated with decreased sperm motility in healthy men, but a relationship between vitamin D and calcium with semen quality and especially sex steroids has not been sufficiently described in infertile men.

Study Design, Size, Duration: This study comprises baseline characteristics of 1427 infertile men screened from 2011 to 2014 for inclusion in a randomized clinical trial, the Copenhagen-Bone-Gonadal Study.

Self-reported onset of puberty and subsequent semen quality and reproductive hormones in healthy young men.

Study Question: Is there an association between pubertal onset and subsequent reproductive health in young men?

Summary Answer: Self-reported later onset of puberty was associated with reduced semen quality and altered serum levels of reproductive hormones among 1068 healthy, young Danish men.

What Is Known Already: The long-term effects of variations in the onset of male puberty on subsequent reproduction remain largely unstudied.

Study Design, Size, Duration: In a cross-sectional study, young healthy Danish men were approached when they attended a compulsory medical examination to determine their fitness for military service from 2008 to 2012.

Obesity and Bariatric Surgery Drive Epigenetic Variation of Spermatozoa in Humans.

Obesity is a heritable disorder, with children of obese fathers at higher risk of developing obesity. Environmental factors epigenetically influence somatic tissues, but the contribution of these factors to the establishment of epigenetic patterns in human gametes is unknown. Here, we hypothesized that weight loss remodels the epigenetic signature of spermatozoa in human obesity.

Psychological stress and testicular function: a cross-sectional study of 1,215 Danish men.

Objective: To study the associations between self-reported psychological stress, semen quality, and serum reproductive hormones among young Danish men.

Design: Cross-sectional study.

Setting: University hospital-based research center.

Association Between Use of Marijuana and Male Reproductive Hormones and Semen Quality: A Study Among 1,215 Healthy Young Men.

A total of 1,215 young Danish men aged 18-28 years were recruited between 2008 and 2012 when they attended a compulsory medical examination to determine their fitness for military service. The participants delivered a semen sample, had a blood sample drawn, and underwent a physical examination. They responded to questionnaires including information on marijuana and recreational drug use during the past 3 months (no use, use once per week or less, or use more than once per week).

Association of sleep disturbances with reduced semen quality: a cross-sectional study among 953 healthy young Danish men.

Several studies have found an association between sleep duration and morbidity and mortality, but no previous studies have examined the association between sleep disturbances and semen quality. We conducted a cross-sectional study among 953 young Danish men from the general population who were recruited in Copenhagen at the time of determination of fitness for military service between January 2008 and June 2011. All of the men delivered a semen sample, had a blood sample drawn, underwent a physical examination, and answered a questionnaire including information about sleep disturbances.

[Male infertility].

In recent years approximately 8% of the newborn Danes have been conceived by infertility treatment, and approximately half of the cases are due to male subfertility. Male infertility can be caused by several factors, and only in about half of the cases is it possible to disclose an aetiological explanation. It is important to elucidate possible reasons for male infertility as low semen quality might be a symptom of pituitary dysfunction, genetic disorders or testicular cancer.

Regional differences and temporal trends in male reproductive health disorders: semen quality may be a sensitive marker of environmental exposures.

The decline in semen quality has been the subject of an animated debate. A recent prospective study now irrefutably shows a decline in semen quality in men from Finland, a country that previously boasted good semen quality. Semen quality has, in some countries, reached a level where a considerable fraction of young men are at risk of fertility problems.