BMI in relation to sperm count: an updated systematic review and collaborative meta-analysis

Effects of bariatric surgery on sexual function and fertility: A narrative review

Obesity has emerged as a prevalent global health concern, with its detrimental effects on the reproductive system and sexual function garnering increasing attention. Both men and women affected by obesity face a heightened risk of fertility challenges and sexual dysfunction. Although fertility and sexual function are distinct topics, they are intricately linked and mutually influential in both medical and societal contexts. Bariatric surgery (BS) has generated promising results in alleviating sexual dysfunction and enhancing fertility, results which are often gender specific. In men, improvements in sexual function can often be attributed to weight loss and subsequent optimizations in sex hormone levels. However, improving female sexual function may be related to a range of factors beyond weight loss. Bariatric procedures have shown limited benefits for male fertility; in fact, in some situations it can even be detrimental, leading to a decrease in sperm count and quality. Conversely, BS may positively impact female fertility, improving pregnancy and neonatal outcomes. Nevertheless, it is essential to consider the potential risks related to the adverse effects of malnutrition and rapid weight loss following BS, making it advisable to wait for 12-18 months before attempting pregnancy.

Association between body mass index and semen quality: a systematic review and meta-analysis

The continuous decline of human semen quality during the past decades has drawn much concern globally. Previous studies have suggested a link between abnormal BMI and semen quality decline, but the results remain inconsistent. This systematic review and meta-analysis aimed to evaluate the association between body mass index (BMI) and semen quality. We searched PubMed, Embase, and Web of Science for eligible studies from inception to April 17, 2022. We considered men with BMI < 25.0 kg/m2 as the reference and calculated the pooled weighted mean difference of men with overweight (BMI 25.0-29.9 kg/m2), obesity (BMI ≥ 30.0 kg/m2), class I obesity (BMI 30.0-34.9 kg/m2), and class II/III obesity (BMI ≥ 35.0 kg/m2). A total of 5070 articles were identified, of which 50 studies were included (71,337 subjects). Compared with men with BMI < 25.0 kg/m2, men with obesity had an average reduction of 0.24 ml in semen volume, 19.56 × 106 in total sperm number, 2.21% in total motility, 5.95% in progressive motility, and 1.08% in normal forms, respectively, while men with overweight had an average reduction of 0.08 ml in semen volume and 2.91% in progressive motility, respectively. The reduction of semen quality was more pronounced among men with obesity than that among men with overweight. Moreover, significant reductions in semen quality were identified in men with different classes of obesity, which were more pronounced in men with class II/III obesity than that in men with class I obesity. Across men from the general population, infertile or subfertile men, and suspiciously subfertile men, we identified significant semen quality reductions in men with obesity/overweight. In conclusion, obesity and overweight were significantly associated with semen quality reductions, suggesting that maintaining normal weight may help prevent semen quality decline.

The relationship between follicle-stimulating hormone and metabolic dysfunction-associated fatty liver disease in men

OBJECTIVES

The present study aimed to investigate the relationship between male hormones and metabolic dysfunction-associated fatty liver disease (MAFLD) in males.

METHODS

Data from the Fangchenggang Area Male Health and Examination Survey (FAMHES) were used to analyze the male hormone levels between MAFLD patients and controls. Univariate and multivariate logistic regression analyses were performed to identify risk factors for MAFLD. Receiver operating characteristic curve analysis was used to assess the diagnostic performance of male hormones for MAFLD.

RESULT

A total of 1578 individuals were included, with 482 individuals (30.54%) of MAFLD, including 293 (18.57%) with mild disease and 189 (11.98%) with moderate-to-severe disease. The MAFLD patients were significantly older than those without MAFLD. The LH, FSH, and SHBG levels in the MAFLD patients were significantly greater than those in the control group. Age, FSH, LH, SHBG, and estradiol were all risk factors for MAFLD. Age, FSH, and LH were risk factors for moderate-to-severe MAFLD. FSH was an independent risk factor for MAFLD and moderate-to-severe MAFLD. FSH showed an excellent diagnostic value, with an AUC of 0.992 alone and 0.996 after adjusting age.

CONCLUSIONS

Our findings indicate that FSH may be a potential diagnostic and predictive biomarker for MAFLD.

Obesity Alters POMC and Kisspeptin Neuron Cross Talk Leading to Reduced Luteinizing Hormone in Male Mice

Obesity is associated with hypogonadism in males, characterized by low testosterone and sperm number. Previous studies determined that these stem from dysregulation of hypothalamic circuitry that regulates reproduction, by unknown mechanisms. Herein, we used mice fed chronic high-fat diet, which mimics human obesity, to determine mechanisms of impairment at the level of the hypothalamus, in particular gonadotropin-releasing hormone (GnRH) neurons that regulate luteinizing hormone (LH), which then regulates testosterone. Consistent with obese humans, we demonstrated lower LH, and lower pulse frequency of LH secretion, but unchanged pituitary responsiveness to GnRH. LH pulse frequency is regulated by pulsatile GnRH secretion, which is controlled by kisspeptin. Peripheral and central kisspeptin injections, and DREADD-mediated activation of kisspeptin neurons, demonstrated that kisspeptin neurons were suppressed in obese mice. Thus, we investigated regulators of kisspeptin secretion. We determined that the LH response to NMDA was lower in obese mice, corresponding to fewer glutamate receptors in kisspeptin neurons, which may be critical for kisspeptin synchronization. Given that kisspeptin neurons also interact with anorexigenic POMC neurons, which are affected by obesity, we examined their cross talk, and determined that the LH response to either DREADD-mediated activation of POMC neurons or central injection of αMSH, a product of POMC, is abolished in obese mice. This was accompanied by diminished levels of αMSH receptor, MC4R, in kisspeptin neurons. Together, our studies determined that obesity leads to the downregulation of receptors that regulate kisspeptin neurons, which is associated with lower LH pulse frequency, leading to lower LH and hypogonadism.

Molecular insights into Sertoli cell function: how do metabolic disorders in childhood and adolescence affect spermatogonial fate?

Male infertility is a major public health concern globally with unknown etiology in approximately half of cases. The decline in total sperm count over the past four decades and the parallel increase in childhood obesity may suggest an association between these two conditions. Here, we review the molecular mechanisms through which obesity during childhood and adolescence may impair future testicular function. Several mechanisms occurring in obesity can interfere with the delicate metabolic processes taking place at the testicular level during childhood and adolescence, providing the molecular substrate to hypothesize a causal relationship between childhood obesity and the risk of low sperm counts in adulthood.

1-DNJ Alleviates Obesity-Induced Testicular Inflammation in Mice Model by Inhibiting IKKβ/ NF-kB Pathway

Obesity is associated with chronic inflammation that affects various organs in the body, including the reproductive system, which is a key factor in male infertility. 1-Deoxynojirimycin (1-DNJ) is a natural alkaloid in mulberry leaves, which has anti-inflammatory capabilities, yet, it's effects on obesity-induced inflammation-related male infertility remain unclear. Therefore, this research investigates the underlying mechanism by which 1-DNJ may mitigate fertility impairment in male mice caused by obesity-related inflammation. Male mice with high-fat diet (HFD)-induced obesity were treated with 1-DNJ or metformin for 8 weeks. Metabolic profiles were evaluated by enzyme method. Reproductive capacity was assessed by sperm viability, motility and counts, immunohistochemistry was performed to evaluate the testicular damage caused by obesity and inflammation. The inflammation was assessed by measuring the levels of tumor necrosis factor α (TNFα), interleukin 1β (IL-1β), and interleukin 6 (IL-6). The activation of IκB kinase β (IKKβ) and nuclear factor κB (NF-κB) was examined using western blot and immunohistochemistry. HFD induced obesity in mice with obvious lipid metabolism disorder. The obese male mice had a decreased testosterone level, impaired sperm motility, and increased inflammatory factors. 1-DNJ treatment improved the testosterone level in the obese mice, ameliorated the testicular structure damage and improve sperm viability. In addition, 1-DNJ treatment inhibited IKKβ/NF-kB signaling pathway and reduced inflammation in obese mice. 1-DNJ can improve the fertility of obese men by reducing obesity as well as obesity-induced inflammation. These findings provide new insights for 1-DNJ to alleviate inflammation caused by obesity and provide future possibilities for treating male infertility.

Machine learning approach to assess the association between anthropometric, metabolic, and nutritional status and semen parameters

Many lifestyle factors, such as nutritional imbalance leading to obesity, metabolic disorders, and nutritional deficiency, have been identified as potential risk factors for male infertility. The aim of this study was to evaluate the relationship between semen parameters and anthropometric, metabolic and nutritional parameters. Relationship was first assessed individually, then after the application of a previously constructed and validated machine learning score that allows their combination. Anthropometric, metabolic, antioxidant, micronutrient, and sperm parameters from 75 men suffering from idiopathic infertility from four infertility centers in France (Jean-Verdier ART Center Hospital, Bondy; North Hospital ART Center, Saint-Étienne; Navarre Polyclinic ART Center, Pau; and Cochin Hospital ART Center, Paris) between September 2009 and December 2013 were collected. After assessing standard correlation analysis, a previously built machine learning model, providing a score ranging from 0 (the poorest) to 1 (the most favorable), was calculated for each man in the study cohort. This machine learning model, which separates infertile/fertile men with unexplained infertility on the basis of their bioclinical signature, provides a more holistic evaluation of the influence of the considered markers (anthropometric, metabolic, and oxidative status). We observed a significant correlation of some anthropometric, metabolic, and nutritional disorders with some sperm characteristics. Moreover, an unfavorable machine learning score was associated with a high level of sperm DNA fragmentation. Favorable anthropometric, metabolic, and oxidative patterns, which may reflect an appropriate lifestyle, appear to positively impact overall health, in particular reproductive function. This study, consistent with previous publications, suggests that beyond semen quality parameters, in an essential assessment of male fertility, other key factors should be taken into account. In this regard, the application of emerging artificial intelligence techniques may provide a unique opportunity to integrate all these parameters and deliver personalized care.

Increased serum creatinine associated with testicular microlithiasis in adult Japanese men: A retrospective cohort study

BACKGROUND

Testicular microlithiasis (TM) is thought to be associated with testicular tumors and impaired spermatogenesis; however, its etiology remains unclear.

OBJECTIVES

To identify factors, other than testicular function, that are associated with testicular microlithiasis.

MATERIALS AND METHODS

We enrolled males who underwent ultrasound examination of the scrotum at Tokyo Dental College Ichikawa General Hospital. The patients were categorized into two groups: those with or those without testicular microlithiasis. Background and blood test data were compared between the groups.

RESULTS

Testicular microlithiasis was observed in 72 of the 828 (8.7%) patients enrolled. Ages ranged from 15 to 87 years (mean age, 40.0 years). A history of germ cell tumor was significantly more prevalent in patients with testicular microlithiasis than in those without (1.3 vs. 16.7%; p < 0.001). Blood test data showed that, patients with testicular microlithiasis had significantly higher serum creatinine levels (0.91 vs. 1.04 mg/dL; p = 0.046) and lower calcium levels (9.4 vs. 9.3 mg/dL; p = 0.031) than those without. Serum creatinine levels (> 1.00 mg/dL) and germ cell tumors were significantly associated with testicular microlithiasis in both univariate and multivariate analyses. The prevalence of testicular microlithiasis increased in patients older than 50 years. Age (> 50 years) was associated with testicular microlithiasis in univariate analysis. The mean body weight tended to be heavier (70.7 vs. 72.2 kg; p = 0.051) and epididymitis was observed more frequently (3.2 vs. 8.3%; p = 0.056) in patients with testicular microlithiasis than in those without.

DISCUSSION AND CONCLUSION

A history of testicular tumors and elevated serum creatinine levels were associated with testicular microlithiasis. Testicular microlithiasis was observed across all age groups, with a tendency to increase in patients older than 50 years. Patients with testicular microlithiasis were slightly heavier and had a higher prevalence of epididymitis than those without. Our findings suggest that, in addition to testicular dysgenesis, other factors are involved in the development of testicular microlithiasis.

Obesity and male fertility disorders

Often associated with obesity, male infertility represents a widespread condition that challenges the wellbeing of the couple. In this article, we provide a comprehensive and critical analysis of studies exploring the association between obesity and male reproductive function, to evaluate the frequency of this association, and establish the effects of increased body weight on conventional and biofunctional sperm parameters and infertility. In an attempt to find possible molecular markers of infertility in obese male patients, the numerous mechanisms responsible for infertility in overweight/obese patients are reviewed in depth. These include obesity-related functional hypogonadism, insulin resistance, hyperinsulinemia, chronic inflammation, adipokines, irisin, gut hormones, gut microbiome, and sperm transcriptome. According to meta-analytic evidence, excessive body weight negatively influences male reproductive health. This can occurr through a broad array of molecular mechanisms. Some of these are not yet fully understood and need to be further elucidated in the future. A better understanding of the effects of metabolic disorders on spermatogenesis and sperm fertilizing capacity is very useful for identifying new diagnostic markers and designing therapeutic strategies for better clinical management of male infertility.

Causal association between 25-Hydroxyvitamin D and risk of abnormal spermatozoa: A bidirectional Mendelian randomization study

Previous studies indicated conflicting findings regarding the association between vitamin D and abnormal spermatozoa. Herein, we assessed the causal association between circulating 25-Hydroxyvitamin D (25OHD) levels and the risk of abnormal spermatozoa by utilizing bidirectional Mendelian randomization (MR) analysis. Genome-wide association study summary statistics for 25OHD and abnormal spermatozoa were obtained from publicly accessible databases. Single nucleotide polymorphisms (SNPs) associated with 25OHD and SNPs associated with abnormal spermatozoa were used as instrumental variables (IVs) for forward MR analysis and reverse MR analysis, respectively. Inverse variance weighted (IVW) was the main MR approach, while weighted median, MR-Egger, and maximum likelihood methods were employed to supplement IVW. In addition, several sensitivity tests assessed the reliability of MR analysis. Forward MR analysis showed that elevated 25OHD levels significantly reduced abnormal spermatozoa risk (odds ratio [OR] = 0.75, 95 % confidence interval [CI]: 0.56-1.00, P = 4.98E-02), and the effect remained statistically significant after excluding SNPs associated with confounders (OR = 0.73, 95 % CI: 0.54-0.98, P = 3.83E-02) or only utilizing SNPs located near 25OHD-associated genes only as IVs (OR = 0.58, 95 % CI: 0.41-0.81, P = 1.67E-03). Reverse MR analysis indicated abnormal spermatozoa not affecting 25OHD level (P > 0.05). Sensitivity tests showed that MR analyses were not affected by heterogeneity and horizontal polytropy. Overall, the present MR study supports that elevated 25OHD levels reduce the risk of abnormal spermatozoa. Therefore, ensuring adequate vitamin D intake and maintaining stable levels of 25OHD may be effective strategies to optimize reproductive outcomes.

Changes in Sperm Parameters with Time in Men with Normal and Abnormal Baseline Semen Analysis

The association between paternal age and sperm quality in the population level has been previously studied. Only limited data exists regarding the intra-personal variations in semen parameters among fertile and infertile men over time. We aimed to assess trends over time in semen parameters among men with normal and abnormal baseline sperm parameters and investigate potential risk factors for sperm quality deterioration. This retrospective cohort study was conducted at a university-affiliated medical center in vitro fertilization (IVF) unit. Patients with at least two semen analyses (SA) performed > 1 year apart, with the last SA done between 2017 and 2021, were included. The study consisted of two main analyses-comparison of intra-patient's sperm parameters changes in men with normal and abnormal baseline SA (BSA) and analysis of risk factors for developing abnormal semen parameters over time in men who had normal BSA parameters. This study included a total of 902 men assessed for infertility with normal and abnormal BSA. The average time interval between tests was 1015 days (range 366-7709 days). Among individuals with normal BSA, there was a mild decline in most parameters-concentration (- 6.53 M/ml), motility (- 7.74%), and total motile count (TMC) (- 21.80 M) (p < 0.05 for all parameters). In contrast, a slight improvement in most parameters, except for concentration, was noted in men with abnormal BSA-volume (+ 0.21 ml), motility (+ 8.72%), and TMC (+ 14.38 M) (p < 0.05 for all parameters). Focusing on men with normal BSA, 33.5% of individuals developed abnormality in one or more of their sperm parameters over time, within a mean time of 1013 ± 661 days. We also found that only time between tests emerged as an independent prognostic factor for the development of abnormal SA later. Interestingly, sperm deterioration in participants in their third, fourth, and fifth decades of life with normal initial semen analysis was similar. Our study provides evidence of a decline in semen quality over time in individuals with normal BSA, in contrast to men with abnormal BSA. Longer time intervals between tests independently increase the risk of sperm abnormalities.

Effects of Calorie Restriction on Preserving Male Fertility Particularly in a State of Obesity

PURPOSE OF REVIEW

Highlight the importance of exploring nutritional interventions that could be applied as alternative or supplementary therapeutic strategies to enhance men's fertility.

RECENT FINDINGS

Lifestyle choices have prompted extensive discussions regarding its implications and applications as a complementary therapy. The growing concern over the decline in sperm quality underscores the urgency of investigating these alternative interventions. Calorie restriction (CR) has emerged as a promising strategy to improve male fertility. The efficacy of CR depends on factors like age, ethnicity and genetics. Clinical studies, such as CALERIE, have shown an improvement in serum testosterone level and sexual drive in men with or without obesity. Additionally, CR has been shown to positively impact sperm count and motility; however, its effects on sperm morphology and DNA fragmentation remain less clear, and the literature has shown discrepancies, mainly due to the nature of technically dependent assessment tools. The review advocates a personalized approach to CR, considering individual health profiles to maximize its benefits. It underscores the need for routine, accessible diagnostic techniques in male reproductive health. It suggests that future research should focus on personalized dietary interventions to improve male fertility and overall well-being in individuals with or without obesity and unravel CR's immediate and lasting effects on semen parameters in men without obesity.

Interplay between male gonadal function and overall male health

The process-of-male reproduction is intricate, and various medical conditions-have the potential to disrupt spermatogenesis. Moreover, infertility in males can serve as an indicator of-potential future health issue. Numerous conditions with systemic implications have been identified, encompassing genetic factors (such as Klinefelter Syndrome), obesity, psychological stress, environmental factors, and others. Consequently, infertility assessment-presents an opportunity for comprehensive health counseling, extending-beyond discussions about reproductive goals. Furthermore, male infertility has been suggested as a harbinger of future health problems, as poor semen quality and a diagnosis of-male infertility are associated with an increased risk of hypogonadism, cardiometabolic disorders, cancer, and even mortality. This review explores the existing-literature on the relationship between systemic illnesses and male fertility, impacting both clinical-outcomes and semen parameters. The majority of the literature analyzed, which compared gonadal function with genetic, chronic, infectious or tumoral diseases, confirm the association between overall male health and infertility.

A combination of gliclazide and metformin attenuates obesity-induced polycystic ovary syndrome in female Wistar rats

Presently, it is known that the progression of obesity concomitantly leads to polycystic ovary syndrome and infertility. This study aimed to evaluate the potential effects of metformin (M; insulin secretagogues) and gliclazide (G; insulin sensitizer) alone and their combination at different doses to treat obesity-induced PCOS. High high-fat diet was given to all female Wistar rats for nine weeks to induce obesity except for the normal control group which received a normal chow diet. Estradiol valerate (0.8 mg/kg) was also given to all obese rats to induce polycystic ovarian syndrome. After the induction, M (100, 300 mg/kg) and G (5, 10 mg/kg) were given orally either individually or in combination for 28 days. The notable (p < 0.0001) reduction in body weight and blood glucose level was observed in treatment groups in contrast to disease control (DCG). The marked (p < 0.05-0.0001) decrease in hemocylated hemoglobin, serum insulin, cholesterol, triglycerides, and testosterone was observed in treated groups, notably in combination groups (M100+G10 mg/kg) in contrast to DCG. There was a considerable (p < 0.01-0.0001) increase in progesterone E2, estradiol, luteinizing, and follicle-stimulating hormones in treated groups as compared to DCG. Treatment with M and G treated groups also exhibited marked (p < 0.05-0.0001) increases in SOD, CAT, and GSH while decreased in NO and MDA levels in ovary tissue as evidenced by the histological study of the ovary. Treatment with M and G alone and in combination significantly (p < 0.0001) restored the serum IL-6, NrF2, and NF-κB levels as compared to DCG. The results inveterate that the M and G combination (M100+G10, and M300+G10) was useful in treating obesity-induced infertility due to antioxidant properties, hypolipidemic effects, and modulation of inflammatory markers.

The influence of lifestyle and biological factors on semen variability

PURPOSE

Semen parameters are subjected to within-individual variability over time. The driving factors for this variability are likely multi-factorial, with healthier lifestyle associated with better semen quality. The extent in which variations in individual's lifestyle contributes to within-individual semen variability is unknown.

METHODS

A total of 116 repeat semen samples from 29 men aged 19-37 over 6 months were collected. Basic semen analysis as per 5th WHO manual and extended semen parameters (sperm DNA fragmentation, redox potential and lipid peroxidation, sperm binding to hyaluronan and hyperactive motility) were assessed. An additional 39 lifestyle/biological factors (weight, blood pressure, etc.) were collected at each sample including validated health questionnaires SF36 Health Status, Australian Recommend Food Score, and International Physical Activity Questionnaire.

RESULTS

Only 10 out of the 39 lifestyle factors varied within men across samples including age (P = 0.0024), systolic blood pressure (P = 0.0080), social functioning (P = 0.0340), energy (P = 0.0069), non-alcoholic caffeinated beverages (P = 0.0010), and nutrition (P < 0.0001). The only semen parameter that varied between collections was sperm morphology (coefficient of variation 23.8 (6.1-72.0), P < 0.05). We only observed weak (r < 0.3) to moderate (r > 0.3- < 0.6) correlations between lifestyle factors, including body mass index, waist circumference, nutrition, exercise, blood pressure and semen parameters including sperm count, progressive motility, and sperm DNA fragmentation (P < 0.05).

CONCLUSION

In healthy men from the general population, semen quality and associated lifestyle factors do not significantly vary over 6 months, indicating that one semen sample is likely sufficient for determining male fertility in this population.

A ripple effect? The impact of obesity on sperm quality and function

Infertility affects approximately 15% of couples trying to conceive. Male-related causes account for roughly 50% of cases, with obesity emerging as a possible significant factor. Obesity, defined as a body mass index of 30.0 or higher, has become a widespread epidemic associated with numerous health issues, including a decrease of fertility. This review discusses the relationship between obesity and male infertility, particularly focusing on sperm quality and function. An overview of the literature suggests that obesity may influence the male reproductive system via disruptions in hormonal profiles, oxidative stress, and inflammation, leading to changes in sperm parameters. Several studies have discussed if obesity causes a decrease in sperm concentration, motility, and normal morphology, so far without a consensus being reached. However, available evidence suggests an impairment of sperm function in obese men, due to an increase in DNA damage and oxidative stress, impaired mitochondrial function and acrosome reaction in response to progesterone. Finally, the relationship between obesity and assisted reproductive technologies outcomes remains debatable, with conflicting evidence regarding the influence on fertilisation, pregnancy, and live birth rates. Therefore, the actual impact of obesity on human spermatozoa still needs to be clarified, due to the multiple factors potentially in play.

Low-dose polystyrene microplastics exposure impairs fertility in male mice with high-fat diet-induced obesity by affecting prostate function

The harmful effects of microplastics (MPs) on male fertility are receiving more and more attention. However, the impact of low-dose MPs exposure on the reproductive function of male mice is still unclear. In this study, we exposed male mice to low-dose MPs (25-30 μg/kg body weight/day) or low-dose MPs combined with high-fat diet (HFD) feeding. Our results showed that low-dose MPs exposure or HFD feeding significantly reduced sperm quality and the number of offspring born, while low-dose MPs exposure combined with HFD feeding further enhanced the above effects. The combination of low-dose MPs exposure and HFD feeding resulted in a notable elevation of inflammatory level within the prostate of mice and induced apoptosis of prostate epithelium and a decrease in nutrients (zinc, citrate) in seminal plasma fluid. Our findings in this study could provide valuable clues for better understanding the influence of low-dose MPs exposure on the reproductive system under metabolic disorders and facilitate the development of the prevention of reproductive toxicity caused by MPs exposure.

Signatures of metabolic diseases on spermatogenesis and testicular metabolism

Diets leading to caloric overload are linked to metabolic disorders and reproductive function impairment. Metabolic and hormonal abnormalities stand out as defining features of metabolic disorders, and substantially affect the functionality of the testis. Metabolic disorders induce testicular metabolic dysfunction, chronic inflammation and oxidative stress. The disruption of gastrointestinal, pancreatic, adipose tissue and testicular hormonal regulation induced by metabolic disorders can also contribute to a state of compromised fertility. In this Review, we will delve into the effects of high-fat diets and metabolic disorders on testicular metabolism and spermatogenesis, which are crucial elements for male reproductive function. Moreover, metabolic disorders have been shown to influence the epigenome of male gametes and might have a potential role in transmitting phenotype traits across generations. However, the existing evidence strongly underscores the unmet need to understand the mechanisms responsible for transgenerational paternal inheritance of male reproductive function impairment related to metabolic disorders. This knowledge could be useful for developing targeted interventions to prevent, counteract, and most of all break the perpetuation chain of male reproductive dysfunction associated with metabolic disorders across generations.

Urinary concentrations of bisphenol A, parabens and benzophenone-type ultra violet light filters in relation to sperm DNA fragmentation in young men: A chemical mixtures approach

People are daily exposed to multiple endocrine disruptor compounds (EDCs) that may interfere with different molecular and cellular processes, promoting a potential estrogenic, androgenic, or anti-androgenic state. However, most epidemiological studies attempting to establish relationships between EDCs exposure and health effects are still considering individual compounds. A few studies have shown associations between exposure to individual non-persistent EDCs and sperm DNA fragmentation (SDF) in different male populations. Thus, the aim of this study was to investigate associations between combined exposure to non-persistent EDCs and SDF index in young men. A cross-sectional study was conducted with 158 healthy university students from Southeaster Spain. The participants provided spot urine and semen samples on the same day. The concentrations of urinary bisphenol A (BPA), benzophenones [2,4-dihydroxybenzophenone (BP-1); 2,2',4,4'-tetrahydroxybenzophenone (BP-2), 2-hydroxy-4-methoxybenzophenone (BP-3), 2,2'-dihydroxy-4-methoxybenzophenone (BP-8), 4-hydroxybenzophenone (4OHBP)], and parabens (methylparaben, ethylparaben, propylparaben, butylparaben) were measured by dispersive liquid-liquid microextraction and ultrahigh-performance liquid chromatography with tandem mass spectrometry detection. SDF was analysed using a Sperm Chromatin Dispersion test. Statistical analyses were carried out using Bayesian Kernel Machine Regression models to evaluate associations between combined exposure to these compounds and SDF index while adjusting by relevant covariates. The increase in urinary concentration of 4OHBP was found to be the most important contributor to the negative association between urinary EDCs concentrations and SDF index, being of -5.5 % [95 % CI: -10.7, -0.3] for those in percentile 50, and - 5.4 % [95 % CI: -10.8, -0.1] for those in percentile 75. No significant associations were observed between other EDCs and SDF index. Our findings show that urinary 4OHBP levels may be associated with a decrease in the SDF index. Nonetheless, the effects we observed were likely to be small and of uncertain clinical significance. Further research is needed to replicate our findings in other male populations.

Improvements in Sperm Motility Following Low- or High-Intensity Dietary Interventions in Men With Obesity

INTRODUCTION

Obesity increases risks of male infertility, but bariatric surgery does not improve semen quality. Recent uncontrolled studies suggest that a low-energy diet (LED) improves semen quality. Further evaluation within a randomized, controlled setting is warranted.

METHODS

Men with obesity (18-60 years) with normal sperm concentration (normal count) (n = 24) or oligozoospermia (n = 43) were randomized 1:1 to either 800 kcal/day LED for 16 weeks or control, brief dietary intervention (BDI) with 16 weeks' observation. Semen parameters were compared at baseline and 16 weeks.

RESULTS

Mean age of men with normal count was 39.4 ± 6.4 in BDI and 40.2 ± 9.6 years in the LED group. Mean age of men with oligozoospermia was 39.5 ± 7.5 in BDI and 37.7 ± 6.6 years in the LED group. LED caused more weight loss than BDI in men with normal count (14.4 vs 6.3 kg; P < .001) and men with oligozoospermia (17.6 vs 1.8 kg; P < .001). Compared with baseline, in men with normal count total motility (TM) increased 48 ± 17% to 60 ± 10% (P < .05) after LED, and 52 ± 8% to 61 ± 6% (P < .0001) after BDI; progressive motility (PM) increased 41 ± 16% to 53 ± 10% (P < .05) after LED, and 45 ± 8% to 54 ± 65% (P < .001) after BDI. In men with oligozoospermia compared with baseline, TM increased 35% [26] to 52% [16] (P < .05) after LED, and 43% [28] to 50% [23] (P = .0587) after BDI; PM increased 29% [23] to 46% [18] (P < .05) after LED, and 33% [25] to 44% [25] (P < .05) after BDI. No differences in postintervention TM or PM were observed between LED and BDI groups in men with normal count or oligozoospermia.

CONCLUSION

LED or BDI may be sufficient to improve sperm motility in men with obesity. The effects of paternal dietary intervention on fertility outcomes requires investigation.

Temporal Trends in Semen Quality, Hormone Levels, and Substance Use Among Infertile Men in Pre- and Post-Cannabis Legalization Eras in Canada

Background: The Cannabis Act (Bill C-45) was enacted in 2018, to legalize and regulate the use, production, and sale of nonmedical cannabis in Canada. While public health and safety implications of cannabis legalization have yet to be elucidated, the wide availability of cannabis necessitates health care providers to be knowledgeable about therapeutic potential and side effects of use. This study aimed to examine the temporal trends over two decades and the impact of the Cannabis Act in Canada, implemented in October 2018, on substance use, semen parameters, and testosterone levels of infertile men. Methods: We conducted a retrospective cohort study from a prospectively maintained database of a single infertility clinic. Demographic, fertility, and substance use history were correlated with semen and hormone assessments. Temporal trends in cannabis use and semen quality between 2001 and 2021 were investigated and compared between pre-cannabis legalization eras (PRCL) and post-cannabis legalization eras (POCL). Results: Our cohort included 11,630 patients (9411 PRCL and 2230 POCL). Cannabis use increased by 8.4% per year (p<0.001), while alcohol and tobacco consumption declined (0.8% and 1.5% per year, p<0.05 and p=0.004, respectively). Similar trends were noticed in the POCL, with higher rates of cannabis use (22.4% vs. 12.9%, p<0.001) and decreased tobacco and alcohol intake (15.2% vs. 17.7%, p=0.005 and 50.5% vs. 55.2%, p<0.001, respectively) compared to the PRCL group. Semen concentration was lower in the POCL group (24.8±44.8 vs. 28.7±48.3 million/mL, p=0.03). Testosterone did not differ between the cohorts. Comparison between cannabis users (n=1715) and nonusers (n=9924) demonstrated a slight increase in sperm motility (25.9%±15.3% vs. 23.9%±15.0%, p=0.002) and decreased sperm concentration among users (27.6±53.5 vs. 23.9±15.0 million/mL, p=0.03). Conclusion: A nearly 10% rise in cannabis use in the POCL era was observed among men being investigated for infertility. Our data suggest cannabis use may be associated with an increase in testosterone, slightly improved sperm motility, and decreased sperm concentration.

Temporal Trends of Semen Quality and Fertility Rates Over the Course of a Decade: Data From King County, Washington

OBJECTIVE

There has been a widely reported decline in both semen quality and fertility rate, however to date these studies have not looked at a decline of both in the same time period within the same geographical area. The objective of this study was to determine if there existed a temporal trend in both semen parameters and fertility rates for the same geographic area (King County, WA) over time.

MATERIALS AND METHODS

Semen parameters from sperm donors at Seattle sperm bank were obtained from 2008 to 2021. Sperm donations occurred in King County, WA. Donors were from within 50 miles of the donation site. Fertility rates were calculated for King County, WA using census data from SEER to find number of women aged 15-49 and the number of births were found using CDC Wonder data from 2006 to 2017.

RESULTS

There were a total of 76,622 sperm donor semen analyses from King County, WA included in our study from 2008 to 2021. The fertility rate for King County, WA was calculated from 2006 to 2017. From 2008 to 2021, there was a statistically significant decline in semen quality over time for both sperm count (P < .01), total motile sperm count (P < .01), sperm concentration (P < .01), and progressive motility (P < .01). Additionally, from 2006 to 2017 there was a statistically significant decline in fertility rate (P < .01).

CONCLUSION

We report a statistically significant decline in sperm parameters among donors and a corresponding decline in fertility rates from the same geographic area that warrants further investigation given the serious societal and economic impacts a shrinking population presents. While certainly not the sole contributing factor, declining sperm parameters likely need to be accounted for when accounting for declining fertility rates.

Childhood Obesity: An Updated Review

BACKGROUND

Childhood obesity is an important and serious public health problem worldwide.

OBJECTIVE

This article aims to familiarize physicians with the evaluation, management, and prevention of childhood.

METHODS

A PubMed search was conducted in May, 2021, in Clinical Queries using the key terms "obesity" OR "obese". The search included clinical trials, randomized controlled trials, case-control studies, cohort studies, meta-analyses, observational studies, clinical guidelines, case reports, case series, and reviews. The search was restricted to English literature and children. The information retrieved from the above search was used in the compilation of the present article.

RESULTS

Most obese children have exogenous obesity characterized by a growth rate for height above the 50th percentile, normal intelligence, normal genitalia, and lack of historical or physical evidence of an endocrine abnormality or a congenital syndrome. Obese children are at risk for dyslipidemia, hypertension, diabetes mellitus, non-alcoholic fatty liver disease, obstructive sleep apnea, psychosocial disturbances, impaired quality of life, and shorter life expectancy. The multitude of serious comorbidities necessitates effective treatment modalities. Dietary modification, therapeutic exercise, and behavioral modification are the fundamentals of treatment. Pharmacotherapy and/or bariatric surgery should be considered for obese individuals who do not respond to the above measures and suffer from a serious comorbid condition.

CONCLUSION

Childhood obesity, once established, is often refractory to treatment. Most treatment programs lead to a brief period of weight loss, followed by rapid re-accumulation of the lost weight after the termination of therapy. As such, preventive activity is the key to solving the problem of childhood obesity. Childhood obesity can be prevented by promoting a healthy diet, regular physical activity, and lifestyle modification. Parents should be encouraged to get involved in school and community programs that improve their children's nutritional status and physical activity.

Nomograms for Predicting Postoperative Sperm Improvements in Varicocele Patients

Background

Varicocele is a condition that seriously affects male fertility. It can cause pathological changes in the testicles and affect their spermatogenesis and endocrine function.

Objective

To formulate nomograms to predict sperm improvements after microscopic varicocelectomy.

Design setting and participants

A retrospective analysis was conducted on varicocele patients who met the research criteria and were enrolled from March 2020 to June 2022. They were divided into a development and a validation cohort in a 2:1 ratio.

Outcome measurements and statistical analysis

Data on preoperative testicular atrophy index, bilateral testicular elastic modulus, testosterone, pre- and postoperative 6-mo total sperm count, sperm concentration, and sperm vitality were collected. An increase of ≥25% is considered a postoperative improvement in sperm parameters. Predictive nomograms were constructed through forward stepwise LR regression, based on independent risk factors filtered by univariate and multivariate logistic regression analyses. Receiver operating characteristic curve analysis, calibration curve, and decision curve analysis were employed to assess the performance of the models.

Results and limitations

The areas under the curve of nomograms for predicting the postoperative improvement of total sperm count, sperm concentration, and sperm vitality were 0.915, 0.986, and 0.924 respectively. The nomogram models demonstrated good predictive performance. The single-center sample size was a limitation of this study.

Conclusions

In this study, we developed effective predictive nomogram models for anticipating postoperative improvements in sperm quality among varicocele patients. These models offer a significant value in providing accurate predictions of surgical outcomes. However, it is crucial to conduct further external validation.

Patient summary

In this study, a predictive nomogram model was constructed for assessing the improvement of sperm quality in varicocele patients after surgery. The model offered satisfactory results.

Implications of Exposure to Air Pollution on Male Reproduction: The Role of Oxidative Stress

Air pollution, either from indoor (household) or outdoor (ambient) sources, occurs when there is presence of respirable particles in the form of chemical, physical, or biological agents that modify the natural features of the atmosphere or environment. Today, almost 2.4 billion people are exposed to hazardous levels of indoor pollution, while 99% of the global population breathes air pollutants that exceed the World Health Organization guideline limits. It is not surprising that air pollution is the world's leading environmental cause of diseases and contributes greatly to the global burden of diseases. Upon entry, air pollutants can cause an increase in reactive oxygen species (ROS) production by undergoing oxidation to generate quinones, which further act as oxidizing agents to yield more ROS. Excessive production of ROS can cause oxidative stress, induce lipid peroxidation, enhance the binding of polycyclic aromatic hydrocarbons (PAHs) to their receptors, or bind to PAH to cause DNA strand breaks. The continuous and prolonged exposure to air pollutants is associated with the development or exacerbation of pathologies such as acute or chronic respiratory and cardiovascular diseases, neurodegenerative and skin diseases, and even reduced fertility potential. Males and females contribute to infertility equally, and exposure to air pollutants can negatively affect reproduction. In this review, emphasis will be placed on the implications of exposure to air pollutants on male fertility potential, bringing to light its effects on semen parameters (basic and advanced) and male sexual health. This study will also touch on the clinical implications of air pollution on male reproduction while highlighting the role of oxidative stress.

Does an increase in adipose tissue 'weight' affect male fertility? A systematic review and meta-analysis based on semen analysis performed using the WHO 2010 criteria

INTRODUCTION

Obesity negatively impact on the metabolism of sex hormones, leading to reduced testosterone serum levels. However, how the obesity could negatively impact on the overall gonadal function, particularly on male fertility, remained unclear so far.

OBJECTIVE

To systematically review evidences regarding the influence of body weight excess on the sperm production.

METHODS

A meta-analysis was conducted, searching all prospective and retrospective observational studies reporting male subjects older than 18 years old, with body weight excess from overweight to severe obesity were considered. Only studies using the V edition of the World Health Organization (WHO) manual for semen analysis interpretation were considered. No specific interventions were considered. Search was focused on studies comparing overweight/obese to normal weight subjects.

RESULTS

Twenty-eight studies were considered. Total sperm count and sperm progressive motility were significantly lower in overweight compared to normal weight subjects. Meta-regression analyses demonstrated that patients' age impacted on sperm parameters. Similarly, obese men showed lower sperm concentration, total sperm number, progressive and total motilities, and normal morphology lower than normal weight subjects. Reduced sperm concentration in obese men was influenced by age, smoking habit, varicocele, and total testosterone serum levels at meta-regression analyses.

CONCLUSIONS

The male potential fertility is reduced in subjects with increased body weight, compared to normal weight men. The higher was the increased body weight, the worst was the sperm quantity/quality. This result comprehensively included obesity among non-communicable risk factor for male infertility, shedding new lights on the negative impact of increased body weight on overall gonadal function.

Impact of GLP-1 Agonists on Male Reproductive Health-A Narrative Review

Background and objective-Obesity is a prevalent health concern that notably impairs male fertility through hormonal disruptions and other pathophysiological alterations. Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) can significantly reduce weight. This narrative review synthesizes the existing literature discussing the impact of glucagon-like peptide-GLP-1 RAs on the male reproductive system, particularly on the hypothalamic-pituitary-gonadal axis and spermatogenesis, highlighting their potential impact on male fertility. Material and methods-PubMed database was used for the retrieval of English-language articles published up to November 2023. This non-systematic literature review predominantly concentrates on both pre-clinical and clinical studies pertaining to GLP-1 RAs, specifically exploring their impact on male reproductive hormones and sperm parameters. Results-GLP-1 receptors have been identified within the male reproductive system according to the existing literature. While the exact mechanisms are not well understood, they appear to be involved in glucose homeostasis and energy metabolism, both vital processes in spermatogenesis. Multiple clinical trials have demonstrated the efficacy of GLP-1 RAs for promoting weight loss. Recent studies show that the use of GLP-1 RAs in obese males may enhance sperm metabolism, motility, and insulin secretion in vitro, along with positive effects on the human Sertoli cells. Recent clinical trials discussed in this review demonstrate weight loss associated with GLP-1 RAs is correlated with improvements in sperm count, concentration, and motility. However, the direct impact of GLP-1 RAs on male reproductive hormones remains unclear, necessitating further research to confirm their potential role in treating male infertility. Conclusions-This narrative review summarizes the existing literature discussing the potential impact of GLP-1 RA on the male reproductive system, emphasizing their potential therapeutic role in addressing idiopathic infertility in obese men. Despite numerous studies exploring the influence of GLP-1 and GLP-1 RAs on reproductive hormones, testicular function, and spermatogenesis, further clinical trials are crucial to validate initial evidence. Longer follow-up periods are essential to address uncertainties regarding the long-term repercussions and outcomes of GLP-1 RA use. While this holds true, the current literature suggests that GLP-1RAs show promise as a potential therapeutic approach for improving sperm parameters in obese men.

The relationship between the intake of dietary fatty acids and minerals with sperm parameters in infertile men

BACKGROUND & AIMS

Infertility has been increasing among Iranian couples. Some epidemiological studies have reported a relationship between infertility and lifestyle patterns, including dietary habits. Our objective was to evaluate the relationship between sperm parameters and the intake of dietary fatty acids and minerals among Iranian infertile men.

METHODS

This cross-sectional was performed on 400 newly diagnosed infertile men at Yazd Reproductive Sciences Institute from July to December 2019. Men whose infertility was confirmed by an andrologist based on the World Health Organization (WHO) criteria were selected. They delivered a semen sample and answered a 168-item semi-quantitative food frequency questionnaire. All data were analyzed using SPSS and STATA software. A p-value of less than 0.5 was considered significant.

RESULTS

In the adjusted model, a significant negative association between sperm motility and the 3rd quartile (Q) of poly-unsaturated fatty acids compared to the 1st quartile) P = 0.02). Also, in the adjusted model, total mobility was significantly increased in the second, third and last quartiles of omega-3 fatty acids compared to the first quartile (P < 0.001, P = 0.02, P < 0.001, respectively). Furthermore, omega-6 fatty acid intake in the last quartile were positively associated with sperm motility (P = 0.01). Moreover, there was a significant association between omega-3 fatty acid intake in the second, third, and last quartiles and sperm normal morphology (P = 0.003, P = 0.018, and P = 0.005, respectively) compared with the first quartile. Further, we observed a significant association between omega-6 fatty acid intake and sperm normal morphology in the last quartile compared with the reference quartile (P = 0.04). Also, the findings showed a significant negative association between the second quartile of sodium and calcium intake and sperm volume compared with the first quartile (P = 0.04, for both) in the adjusted model.

CONCLUSIONS

We concluded that dietary polyunsaturated fatty acid, sodium, and calcium intake are related to sperm morphology, volume, and total motility in Iranian infertile men. However, more research is needed to confirm these relationships and provide evidence to exert these findings into clinical practice.

Articles in the field of infertility (2013-2022): a bibliometric analysis

To carry out an in-depth analysis of the scientific research on infertility, we performed the first bibliometric analysis focusing on studies involving global literature on infertility during the period 2013-2022. Analysis of 33239 articles in the field of infertility showed a significant increasing trend in the number of publications over the period 2013-2022, with authors mainly from the USA and China. Shanghai Jiao Tong University published the most articles. This study is the first to analyze the global field of infertility (2013-2022) from multiple indicators by bibliometrics, thus providing new insights into the research hotspots and development trends in the field of infertility.

Too much or not enough: lifestyle modifications to optimize male fertility

This month's Views and Reviews examines the current literature on modifiable factors that men can do to optimize reproductive health. Gaskins et al. provide an overview of dietary factors, including specific foods, diets, and nutrients associated with male fertility. Service et al. then provided an update on body mass index, weight loss, and male reproduction. Garabed et al. examine the data behind medications using the Anatomical Therapeutic Chemical Classification System. Mínguez-Alarcón et al. reviewed data on chemical exposures and male fertility. Overall, the goal of the section is to allow providers with up-to-date evidence to counsel our patients on factors they can seek or avoid.

The Impact of Obesity on Sperm Parameters in Young Adult Males: A Retrospective Study of Sperm Donors

OBJECTIVE

To utilize a large cohort of healthy sperm bank donors to evaluate the association between body mass index and individual sperm parameters.

METHODS

Sperm parameters from donors across the United States were obtained between 2013 and 2022. Donors were healthy men aged 18-46years old. Semen samples were analyzed in a certified lab following guidelines by the World Health Organization. A multivariable interaction model between age, body mass index, and sperm parameters was conducted.

RESULTS

There were 117,357 sperm donations included in our study. In our sample, 98,397 (83.84%) men were classified as young donors (ages 18-32years) and 18,960 (16.16%) were classified as old donors (ages 33-46years). We identified 1032 (0.88%) men as underweight, 76,635 (65.30%) as normal weight, 36,686 (31.26%) as overweight, and 3004 (2.56%) as obese. Participants had a median total motile sperm count (TMSC) of 186 (interquartile ranges [IQR]: 128 million), volume of 3.36 (IQR: 1.82 mL), sperm concentration of 56 (IQR: 34 million/mL) and a progressive motility of 59.84% (IQR: 16.95%). Older obese donor had lower TMSC (β = -22.98 ± 4.66, P < .001), semen volumes (β = -0.85 ± 0.06, P < .001), and progressive motility (β = -3.94 ± 0.56, P < .001) compared to younger, healthy weight donors.

CONCLUSION

We observed lower TMSC, semen volumes, and progressive motility in older obese donors. Although these values are within the normal expected ranges for individual sperm parameters, our ability to detect differences within this healthy population highlights the importance of maintaining a healthy diet and exercise regimen for preserving high sperm counts.

SPIN-4/Spinster supports sperm activation in C. elegans via sphingosine-1-phosphate transport

Spermiogenesis, a sperm-activation step, is crucial for the transformation of immotile spermatids into motile sperm. Though membrane transport of ions and molecules across the sperm plasma membrane has been implicated in this process, the full repertoire of transporters involved, and their respective substrates, is unclear. Here, we report that the major facilitator superfamily transporter SPIN-4/Spinster governs efficient spermiogenesis and fertility in the hermaphrodite nematode Caenorhabditis elegans. Unlike other C. elegans Spinster paralogs, SPIN-4 is germline-expressed. Moreover, SPIN-4 expression is gamete-specific; it is strongly expressed in developing sperm, where it localizes to the plasma membrane, but it is absent from oocytes. Consistent with these expression data, we demonstrate that knocking out spin-4 impairs sperm development, leading to the formation of non-motile sperm that lack pseudopodia. Consequently, hermaphrodites homozygous for the spin-4(knu1099) knockout allele show extensive sperm wasting and reduced self-progeny. We observe similar defects when we genetically inhibit production of sphingosine-1-phosphate, a lipid molecule that stimulates cell motility when exported extracellularly by Spinster homologs in other contexts. Remarkably, extracellular supplementation with sphingosine-1-phosphate rescues sperm activation and motility in the absence of SPIN-4, suggesting that Spinster-dependent efflux of sphingosine-1-phosphate plays a key role in sperm mobilization. These findings identify a new signaling mechanism in C. elegans spermiogenesis entailing Spinster and sphingosine-1-phosphate.

The effects of male anxiety and depression on IVF outcomes

STUDY QUESTION

What are the effects of male anxiety and depression on IVF outcomes?

SUMMARY ANSWER

Men with anxiety had lower final total motile sperm counts (fTMSC) during IVF compared to men without anxiety; however, there were no differences in live birth rates (LBRs).

WHAT IS KNOWN ALREADY

Studies have shown that male anxiety causes low sperm motility, worse sperm morphology, and increased DNA fragmentation, which are known to be influential factors on fertilization rates and embryo quality during IVF. However, data are lacking on whether there is a direct association between male anxiety and/or depression and IVF outcomes.

STUDY DESIGN, SIZE, DURATION

This was a survey-based, retrospective cohort study completed at a single, large hospital-affiliated fertility center with 222 respondents who underwent IVF with or without ICSI. The study was conducted between 6 September 2018 and 27 December 2022.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Male partners of couples who underwent IVF or IVF/ICSI completed a Hospital Anxiety and Depression Scale (HADS) questionnaire. They were separated into two groups for both anxiety (HADS-A ≥ 8 or HADS-A < 8) and depression (HADS-D ≥ 8 or HADS-D < 8). Men with an elevated HADS-A or HADS-D score ≥8 were considered to have anxiety or depression, respectively. The primary outcome was LBR. Secondary outcomes included semen parameters at the time of IVF, cycle outcomes, pregnancy outcomes, and prevalence of erectile dysfunction and low libido.

MAIN RESULTS AND THE ROLE OF CHANCE

There were a total of 222 respondents, of whom 22.5% had a HADS-A ≥ 8 and 6.5% had a HADS-D ≥ 8. The average age of respondents was 37.38 ± 4.90 years old. Antidepressant use was higher in the respondents with a HADS-A or HADS-D ≥ 8 (P < 0.05). Smoking use was similar between groups for both HADS-A and HADS-D (P > 0.05). When adjusted for male BMI, antidepressant use and smoking, men with a HADS-A or HADS-D ≥ 8 had similar rates of erectile dysfunction (adjusted relative risk (aRR) = 1.12 (95% CI 0.60, 2.06)) and low libido (aRR = 1.70 (95% CI 0.91, 3.15)) compared to those with a HADS-A or HADS-D ≤ 8. Men with a HADS-A ≥ 8 were more likely to have a lower fTMSC on the day of oocyte retrieval (11.8 ≥ 8 vs 20.1 < 8, adjusted ß = -0.66 (95% CI -1.22, -0.10)). However, the LBR per embryo transfer (ET) was similar between the HADS-A groups (43.2% ≥8 vs 45.1% <8, adjusted relative risk = 0.90 (95% CI 0.65, 1.06)). Although depression was uncommon in the entire cohort, the HADS-D groups were clinically similar for fTMSC (18.7 ≥ 8 vs 16.0 < 8) and LBR per ET (46.7% ≥8 vs 45.4% <8).

LIMITATIONS, REASONS FOR CAUTION

Limitations of our study are the survey-based design, the lack of sperm morphology assessment at the time of IVF, our inability to fully assess the HADS-D ≥ 8 cohort due to the small sample size and the large Caucasian demographic.

WIDER IMPLICATIONS OF THE FINDINGS

Couples undergoing IVF have an increased likelihood of suffering from anxiety and/or depression. There is currently a debate on whether or not men should be treated with antidepressants while attempting to conceive due to potential detrimental effects on sperm quality. Our study shows that, regardless of antidepressant use, couples with men who did or did not report anxiety and/or depression have similar LBRs when undergoing IVF. Therefore, it is important to assess both partners for mental health and to not withhold treatment due to a concern about a potential impact of antidepressants or anxiety/depression on sperm quality.

STUDY FUNDING/COMPETING INTEREST(S)

There was no funding to report for this study. Z.W. is a contributing author for UptoDate. S.S.S. is on the advisory board for Ferring Pharmaceuticals. E.G. was a medical consultant for Hall-Matson Esq, Teladoc, and CRICO and is a contributing author for UptoDate. The remaining authors have nothing to report.

TRIAL REGISTRATION NUMBER

N/A.

The Impact of Obesity on Reproductive Health and Pregnancy Outcomes

Women carry the majority of the burden of our obesogenic surroundings, with a larger prevalence of obesity than males, a greater impact on fertility and treatment success, and increased maternal and perinatal morbidity and death. Obesity and its associated morbidity are now among our most pressing global health concerns. Women are more susceptible to gaining weight, which has reproductive, coronary, and emotional consequences. The current data on the negative consequences of obesity before conception (fertility issues, assisted reproductive treatment, polycystic ovary disease, overweight and obesity preventative measures, and emotional well-being), pregnancy (preventing excess gestational body weight, gestational diabetes, and preeclampsia, as well as labor and newborn health), and following delivery (the lactation process and breastfeeding, postnatal weight retention, and depressive symptoms) health is summarized. in this review. Along with this, underlying factors, consequences, and solutions to the obesity pandemic are investigated, as well as the mechanisms of obesity's effect on women and men, the epigenetic consequences of masculine obesity, its significant effects on reproductive results, and the implications of the loss of weight preceding to pregnancy as well as during pregnancy. This review suggests study methodologies that might assist in guiding attempts to enhance reproductive health and neonatal health in obese or overweight women.

The effect of ellagic acid on the metabolic syndrome: A review article

Objective

(s): Metabolic syndrome is a collection of metabolic abnormalities that includes hyperglycemia, dyslipidemia, hypertension, and obesity. Ellagic acid is found in various fruits and vegetables. It has been reported to have several pharmacological properties, such as antibacterial, antifungal, antiviral, anti-inflammatory, hepatoprotective, cardioprotective, chemopreventive, neuroprotective, gastroprotective, and antidiabetic. Our current study aims to shed light on the probable efficiency of ellagic acid in managing metabolic syndrome and its complications.

Materials and methods

To prepare the present review, the databases or search engines utilized included Scopus, PubMed, Science Direct, and Google Scholar, and relevant articles have been gathered with no time limit until March 2023.

Results

Several investigations indicated that ellagic acid could be a potent compound for the treatment of many disorders such as diabetes, hypertension, and hyperlipidemia by various mechanisms, including increasing insulin secretion, insulin receptor substrate protein 1 expression, regulating glucose transporter 4, triglyceride, total cholesterol, low-density lipoprotein (LDL), high-density lipoprotein (HDL), attenuating tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), reactive oxygen species (ROS), malondialdehyde (MDA), and oxidative stress in related tissues. Furthermore, ellagic acid ameliorates mitochondrial function, upregulates uncoupling protein 1 (found in brown and white adipose tissues), and regulates blood levels of nitrate/nitrite and vascular relaxations in response to acetylcholine and sodium nitroprusside.

Conclusion

Ellagic acid can treat or manage metabolic syndrome and associated complications, according to earlier studies. To validate the beneficial effects of ellagic acid on metabolic syndrome, additional preclinical and clinical research is necessary.

Male obesity: Associated effects on fertility and the outcomes of offspring

Obesity rates are increasing globally, making it imperative to comprehend the effects of parental obesity on human reproduction. This review aims to highlight the impact of male obesity on reproductive and offspring outcomes. Male obesity has been shown to affect fertility through various mechanisms, including changes in semen quality, difficulty with natural conception, and worsened assisted reproductive technology outcomes. The evidence regarding the impact of male obesity on success of sperm retrieval is conflicting, but all aforementioned adverse effects may be modifiable with weight loss. Moreover, paternal obesity may influence atypical offspring outcomes, such as placental abnormalities and disruptions in fetal development, which may be moderated by epigenetic pathways. Further research is needed to fully understand the complex relationships and underlying mechanisms involved. Gaining more insight into the impact of male obesity on fertility and offspring outcomes can aid in the development of targeted interventions to improve family planning and the health of future generations.

Timing of puberty in relation to semen characteristics, testicular volume, and reproductive hormones: a cohort study

OBJECTIVE

To investigate whether the timing of puberty is associated with semen characteristics, testicular volume, and reproductive hormone levels.

DESIGN

Cohort study.

SETTING

Not applicable.

PATIENTS

The Danish National Birth Cohort and its subcohort, the Fetal Programming of Semen Quality cohort of 1,058 young men.

INTERVENTION(S)

Self-reported information on the timing (younger, same age, older than peers) of the pubertal markers: voice break (primary exposure), pubic hair growth, regular shaving, and axillary hair growth.

MAIN OUTCOME MEASURES(S)

We estimated the relative differences with 95% confidence intervals for semen characteristics (semen volume, sperm concentration, total sperm count, sperm motility, percentage of morphologically normal spermatozoa), testicular volume, and reproductive hormones (follicle stimulating hormone [FSH], luteinizing hormone, sex hormone-binding globulin [SHBG], testosterone, estradiol, and free androgen index [FAI]) obtained at a median age of 19.2 years according to timing of pubertal development.

RESULT(S)

Compared with men reporting voice break "same age as peers," men reporting voice break "older than peers" tended to have lower total sperm count (-12% [-25%, 4%]) and lower percent morphologically normal spermatozoa (-10% [-20%, 2%]), whereas men reporting voice break "younger than peers" tended to have a lower proportion of nonprogressive and immotile spermatozoa (-6% [-13%, 1%]) and larger testicular volume (7% [1%, 13%]). The pattern was less consistent for the other pubertal markers. For reproductive hormones, voice break "older than peers" tended to have higher FSH levels (24% [-1%, 55%]), higher SHBG levels (7% [0, 15%]), lower estradiol levels (-14% [-23%, -5%]), and lower FAI (-8% [-14%, -1%]), whereas voice break "younger than peers" tended to have higher luteinizing hormone levels (4% [-2%, 11%]), higher testosterone levels (5% [0%, 11%]), higher estradiol levels (17% [6%, 29%]), and higher FAI (4% [-2%, 11%]). When the categorical pubertal markers were analyzed as a linear term to assess dose dependence, older age at pubertal development was associated with higher FSH levels, higher SHBG levels, lower testosterone levels, lower estradiol levels, and lower FAI for most pubertal markers.

CONCLUSION(S)

These results lend weak support to the hypothesis that older age at pubertal development is associated with markers of reduced male fecundity, especially reproductive hormone levels, although associations with semen characteristics and testicular volume were statistically insignificant.

Male infertility

Clinical infertility is the inability of a couple to conceive after 12 months of trying. Male factors are estimated to contribute to 30-50% of cases of infertility. Infertility or reduced fertility can result from testicular dysfunction, endocrinopathies, lifestyle factors (such as tobacco and obesity), congenital anatomical factors, gonadotoxic exposures and ageing, among others. The evaluation of male infertility includes detailed history taking, focused physical examination and selective laboratory testing, including semen analysis. Treatments include lifestyle optimization, empirical or targeted medical therapy as well as surgical therapies that lead to measurable improvement in fertility. Although male infertility is recognized as a disease with effects on quality of life for both members of the infertile couple, fewer data exist on specific quantification and impact compared with other health-related conditions.

A North American study of anthropometric factors and semen quality

OBJECTIVE

To evaluate the association between anthropometric measures and semen parameters.

DESIGN

Cross-sectional study.

SUBJECTS

Male participants aged ≥21 years. We analyzed data from 659 males (1185 samples) participating in a semen testing substudy of the Pregnancy Online Study (PRESTO), a North American preconception cohort study. After enrollment, we invited males aged ≥21 years to perform at-home semen testing using the Trak system.

EXPOSURE(S)

Participants reported selected anthropometric variables (current weight, height, waist circumference, and weight at age 17 years) and covariate data via an online baseline questionnaire.

MAIN OUTCOME MEASURE(S)

We used generalized estimating equations models to estimate the percent difference in mean log-transformed semen parameter values and 95% confidence intervals (CI) for associations between selected anthropometric variables and semen volume (mL), sperm concentration (million/mL), and total sperm count (million), adjusting for sociodemographics, lifestyle factors, and medical history. We also evaluated World Health Organization-defined thresholds for low semen quality.

RESULT(S)

Percentage differences in mean log-transformed semen volume, sperm concentration, and total sperm count (95% CI) comparing current body mass index ≥35 vs. <25 kg/m2 were -6.3 (-15.8, 4.3), -6.4 (-24.6, 16.2), and -12.2 (-31.1, 11.8), respectively. Percentage differences (95% CIs) comparing waist circumferences of ≥42 vs. <31 inches were -4.2 (-15.0, 8.0), -6.4 (-27.6, 21.0), and -10.4 (-31.9, 17.9) for semen volume, sperm concentration, and total sperm count, respectively. Greater adult weight gain since age 17 years was associated with reduced semen volume (≥25 vs. <5 kg; percent difference, -9.7; 95% CI, -18.4, 0.1), but not sperm concentration or total sperm count. The highest categories of each anthropometric variable generally were associated with World Health Organization-defined low total sperm count (≤39 million).

CONCLUSION(S)

Selected anthropometric factors were associated modestly with poorer semen quality.

Reproduction as a window for health in men

Male factor infertility is widely considered a harbinger for a man's general health. Failure of reproduction often accompanies other underlying processes, with growing evidence suggesting that a diagnosis of infertility increases the likelihood of developing future cardiac, metabolic, and oncologic diseases. The goal of this review is to provide a comprehensive overview of the research on male fertility as a marker for current and future health. A multidisciplinary approach is essential, and there is growing consensus that the male fertility evaluation offers an opportunity to better men's wellness beyond their immediate reproductive ambitions.

Maternal cardiovascular disorders before and during pregnancy and offspring cardiovascular risk across the life course

Obesity, hypertension, type 2 diabetes mellitus and dyslipidaemia are highly prevalent among women of reproductive age and contribute to complications in >30% of pregnancies in Western countries. An accumulating body of evidence suggests that these cardiovascular disorders in women, occurring before and during their pregnancy, can affect the development of the structure, physiology and function of cardiovascular organ systems at different stages during embryonic and fetal development. These developmental adaptations might, in addition to genetics and sociodemographic and lifestyle factors, increase the susceptibility of the offspring to cardiovascular disease throughout the life course. In this Review, we discuss current knowledge of the influence of maternal cardiovascular disorders, occurring before and during pregnancy, on offspring cardiovascular development, dysfunction and disease from embryonic life until adulthood. We discuss findings from contemporary, large-scale, observational studies that provide insights into specific critical periods, evidence for causality and potential underlying mechanisms. Furthermore, we focus on priorities for future research, including defining optimal cardiovascular and reproductive health in women and men before their pregnancy and identifying specific embryonic, placental and fetal molecular developmental adaptations from early pregnancy onwards. Together, these approaches will help stop the intergenerational cycle of cardiovascular disease.

Clinical and Therapeutic Implications of Male Obesity

The prevalence of obesity, a disorder linked to numerous comorbidities and metabolic complications, has recently increased dramatically worldwide and is highly prevalent in men, even at a young age. Compared to female patients, men with obesity more frequently have delayed diagnosis, higher severity of obesity, increased mortality rate, and only a minority of obese male patients are successfully treated, including with bariatric surgery. The aim of this review was to present the current state of knowledge about the clinical and therapeutic implications of obesity diagnosed in males.

The impact of dietary fructose on gut permeability, microbiota, abdominal adiposity, insulin signaling and reproductive function

The excessive intake of fructose in the regular human diet could be related to global increases in metabolic disorders. Sugar-sweetened soft drinks, mostly consumed by children, adolescents, and young adults, are the main source of added fructose. Dietary high-fructose can increase intestinal permeability and circulatory endotoxin by changing the gut barrier function and microbial composition. Excess fructose transports to the liver and then triggers inflammation as well as de novo lipogenesis leading to hepatic steatosis. Fructose also induces fat deposition in adipose tissue by stimulating the expression of lipogenic genes, thus causing abdominal adiposity. Activation of the inflammatory pathway by fructose in target tissues is thought to contribute to the suppression of the insulin signaling pathway producing systemic insulin resistance. Moreover, there is some evidence that high intake of fructose negatively affects both male and female reproductive systems and may lead to infertility. This review addresses dietary high-fructose-induced deteriorations that are obvious, especially in gut permeability, microbiota, abdominal fat accumulation, insulin signaling, and reproductive function. The recognition of the detrimental effects of fructose and the development of relevant new public health policies are necessary in order to prevent diet-related metabolic disorders.

Obesity and male infertility

The worldwide prevalence of obesity is increasing among both sexes, with associated impacts on chronic health and medical comorbidities. Similarly, the effects of obesity on reproductive health are increasingly being recognized. Adiposity is associated with reduced fertility in men, with a complex and multifactorial etiology. The reported effects of obesity on semen parameters and impaired fertility are contrasting, with some studies showing a clear reduction in reproductive outcomes associated with increased body mass index, while others do not show such impacts. These controversies may be due to the complex pathophysiology and interplay between gonadotropins and end organs, as well as genetic and epigenetic changes and oxidative stress on male fertility and function. These different aspects have led to heterogeneous participants in studies and varying implications for assisted reproductive outcomes as well as offspring health. Treatment modalities to manage obesity include lifestyle, medical, and surgical options, with emerging and effective medical treatments showing promise in reproductive outcomes.

The Price of Human Evolution: Cancer-Testis Antigens, the Decline in Male Fertility and the Increase in Cancer

The increasing frequency of general and particularly male cancer coupled with the reduction in male fertility seen worldwide motivated us to seek a potential evolutionary link between these two phenomena, concerning the reproductive transcriptional modules observed in cancer and the expression of cancer-testis antigens (CTA). The phylostratigraphy analysis of the human genome allowed us to link the early evolutionary origin of cancer via the reproductive life cycles of the unicellulars and early multicellulars, potentially driving soma-germ transition, female meiosis, and the parthenogenesis of polyploid giant cancer cells (PGCCs), with the expansion of the CTA multi-families, very late during their evolution. CTA adaptation was aided by retrovirus domestication in the unstable genomes of mammals, for protecting male fertility in stress conditions, particularly that of humans, as compensation for the energy consumption of a large complex brain which also exploited retrotransposition. We found that the early and late evolutionary branches of human cancer are united by the immunity-proto-placental network, which evolved in the Cambrian and shares stress regulators with the finely-tuned sex determination system. We further propose that social stress and endocrine disruption caused by environmental pollution with organic materials, which alter sex determination in male foetuses and further spermatogenesis in adults, bias the development of PGCC-parthenogenetic cancer by default.

Obesity and Male Infertility: True, True, and Unrelated?

While the prevalence of obesity has rapidly increased worldwide, there has also been a notable decline in semen parameters over the last several decades. While obesity can negatively impact reproductive hormones, many studies have sought a link between rising obesity and decreased male fertility potential. Nonetheless, few data support a direct link between the two. The focus on obesity as a causative factor in male infertility can potentially result in patient harm through delayed fertility treatment and missed diagnoses. This review investigates the associations between obesity and male infertility and why a potential direct link has been elusive and may not exist. Additionally, indirect mechanisms that may link the two will be reviewed and treatment options for obese infertile men presenting for evaluation will briefly be discussed.

Influence of body mass index and waist-hip ratio on male semen parameters in infertile men in the real world: a retrospective study

Background

It is suggested that body mass index (BMI) can affect male semen quality; however, the results remain controversial. In addition, most studies have focused on the effect of obesity on semen quality. Evidence on the relationship of underweight or waist-hip ratio (WHR) with semen quality is rare. This study aimed to assess the association of BMI and WHR with semen quality.

Methods

Data, including BMI and WHR, was collected from 715.00 men who underwent a fertility evaluation. BMI (kg/m²) was categorized as <18.50 (underweight), 18.50-24.90 (normal), 25.00-27.90 (overweight), and ≥28.00 (obese) kg/m² for analysis. WHR was categorized as <0.81 (normal) and ≥0.81 (high). Semen volume, sperm concentration, progressive motility, and total motile sperm count were detected by experienced clinical technicians.

Results

Spearman's correlation showed that BMI was weakly associated with sperm progressive motility (r = 0.076, P < 0.05), while WHR showed no relationship with semen parameters. The azoospermia rate was significantly higher (33.33% vs. 2.10%, P < 0.001) and the sperm concentration was lower (P < 0.05) in the underweight group. The nonlinear correlation analysis showed that BMI was negatively associated with sperm concentration while BMI was more than 22.40 kg/m² (P < 0.05), while WHR was negatively related to sperm progressive motility within 0.82 to 0.89 (P < 0.05). Furthermore, the multivariate logistic analysis showed that follicular stimulating hormone (FSH) was an independent risk factor for normal sperm concentration (odds ratio [OR]: 0.791, P = 0.001) and morphology (OR: 0.821, P = 0.002), BMI was an independent risk factor for normal sperm progressive motility, and testosterone was an independent risk factor for sperm morphology (OR: 0.908, P = 0.023).

Conclusion

BMI and WHR were significantly associated with semen parameters, while BMI was an independent risk factor for normal sperm progressive motility. Reproductive hormones, including FSH and testosterone, had a significant influence on sperm concentration and sperm morphology.

Long-term effect of sleeve gastrectomy surgery on Hormonal Profile, Semen Parameters and sexual functions of obese infertile men; a prospective observational study

BACKGROUND

The effect of bariatric surgery on impaired semen parameters, hormonal profile and sexual function remains controversial to some extent.

THE CONTEXT AND PURPOSE OF THE STUDY

To look at the long-term effects of sleeve gastrectomy on hormonal profiles, sperm parameters, and sexual function in infertile men with severe obesity. This prospective study included fifty-four obese patients with primary or secondary infertility who were scheduled for sleeve gastrectomy between February 2018 and March 2021. All participants were given a sperm analysis and a serum hormone profile before, 12, and 18 months after surgery. We used the International Index of Erectile Function questionnaire to assess sexual function.

RESULTS

There was a significant correlation between weight loss after sleeve gastrectomy and improvement in lipid profile (p < 0.05). No significant detectable effect of post-gastrectomy weight loss on patients with diabetes mellitus, hypertension, or obstructive sleep apnea. As regards the hormonal profile, sex hormone binding globulin, total and free testosterone improved significantly after 12- and 18-months following sleeve gastrectomy. There was a significant increase in sperm count and total sperm number during the follow-up after sleeve gastrectomy (p < 0.05), however, there were no significant changes in other semen parameters. Concerning sexual function, sexual desire, erectile function, and satisfaction improved significantly at 12 and 18 months after surgery.

CONCLUSION

Weight loss through sleeve gastrectomy surgery significantly improves testosterone deficiency, sexual performance, and Sperm count in obese infertile men.

How much obesity and diabetes do impair male fertility?

BACKGROUND

Subfertility in obese and diabetic men during the reproductive age is evident, but the mechanisms by which obesity and diabetes mellitus cause male infertility are not entirely understood. The current study aimed to evaluate the effects and potential mechanisms of obesity and diabetes on male fertility.

METHODS

We enrolled control = 40, obese = 40, Lean-DM = 35, and Obese-DM = 35 individuals. The obesity-associated markers, diabetic markers, hormonal and lipid profile, inflammatory indices, and semen analysis were assessed in four experimental groups.

RESULTS

Our finding showed that diabetic markers were significantly increased in two diabetic groups, while obesity indices were markedly increased in two obese groups. Conventional sperm parameters were significantly lower in three groups compared with the control. Serum levels of total testosterone and sex hormone-binding globulin were significantly lower in men with obesity and DM compared with the control. There was a significant difference in the concentration of high-sensitivity C-reactive protein among four experimental groups. Moreover, serum leptin was significantly increased in obese DM, lean DM, and obese groups. Serum insulin levels had a positive correlation with metabolic-associated indices and high-sensitivity C-reactive protein levels, whereas it had a negative correlation with count, motility, and morphology.

CONCLUSIONS

Our findings showed the metabolic changes, hormonal dysfunction and inflammatory disturbance might be suspected mechanisms of subfertility in obese and diabetic subfertile men.

The influence of lead exposure on male semen parameters: a systematic review and meta-analysis

Lead (Pb) is a metal with a widespread diffusion in the environment. Pb tends to accumulate in the human body and, as a consequence, semen alterations can be present in exposed workers or general population. The aim of the present study is to evaluate the effect on semen parameters among healthy men exposed to environmental or occupational Pb. A systematic literature search was performed on November 12^th, 2022, through MEDLINE via PubMed, Scopus, and Embase. Observational studies comparing semen parameters in men exposed to Pb and those not exposed were included. Sperm parameters were pooled using the Cochran-Mantel-Haenszel Method with a random effect model. The weighted mean difference (WMD) was used as a summary measure. Statistical significance was set at p-value <0.05 Ten papers were included. Pb exposure was associated with a significant reduction in semen volume (WMD -0.76ml.95% CI -1.47, -0.05, p=0.04), sperm concentration (WMD -0.63 ×10⁶/ml 95% CI -1.15, -0.12, p=0.02), total sperm count (WMD -1.94 ×10⁶ 95% CI -3. 77, -0.11, p=0.04), sperm vitality (WMD -2.18% 95% CI -3.92, -0.45, p=0.01), and total sperm motility (WMD -1.31% 95% CI -2.33, -0.30, p=0.01). No difference was found in sperm normal morphology, progressive motility, and seminal viscosity. This review demonstrated the negative effect of Pb exposure on most of semen parameters. Given the diffuse exposure to this metal of the general population, public health concerns should be considered and exposed workers should be assessed to evaluate their semen. DATA AVAILABILITY STATEMENT: Data will be provided by the corresponding author upon a reasonable request.