Effect of Bariatric Surgery on Semen Parameters: A Systematic Review and Meta-Analysis

Effect of surgical, medical, and behavioral weight loss on hormonal and sexual function in men: a contemporary narrative review

This review explores the mechanisms and ramifications of weight loss achieved through lifestyle modifications, medical treatments, and bariatric surgery on testosterone levels and sexual health. Obesity significantly affects the hypothalamic-pituitary-gonadal axis in men, leading to diminished libido and erectile dysfunction. Here, we delve into the physiological disruptions caused by this imbalance and the intricate interplay of hormonal factors contributing to the dysregulation associated with obesity to comprehensively grasp the consequences of weight loss via diverse mechanisms. Lifestyle modifications involving dietary adjustments and regular exercise represent a widely employed and efficacious means of weight loss. While adherence demands discipline, our review scrutinizes various studies specifically investigating the impact of weight loss, attained through lifestyle modifications, on serum hormone levels and sexual function. Notably, several randomized controlled trials within the existing body of literature corroborate the enhancement of testosterone levels and sexual function consequent to weight loss through lifestyle modifications. The realm of medical management in addressing obesity is growing, notably propelled by the popularity of pharmacotherapy. Despite its prevalence, the current literature exploring the effects of weight loss medications on men remains insufficient. Nonetheless, we examine available studies on the medical management of obesity and its implications for sexual health, emphasizing pivotal avenues requiring further investigation. Bariatric surgery stands as an effective approach for individuals seeking substantial weight loss. Our review assesses existing literature that evaluates the impact of various surgical techniques on serum hormone levels, sexual function, and semen parameters. Despite certain limitations, the available body of evidence suggests enhancements in hormone levels and sexual function post-surgery, with semen parameters generally exhibiting minimal changes. This review critically evaluates the landscape of weight loss and its correlation with sexual function, while highlighting crucial areas necessitating future research endeavors.

The impact of obesity and metabolic health on male fertility: a systematic review

The impact of paternal obesity and metabolic disease on semen quality and fertility outcomes is not fully appreciated. With increasing obesity rates, researchers have studied the intricate relationship between paternal body mass index, metabolic health, and male fertility. This systematic review identified 112 articles in the MEDLINE database between 2013 and 2023 that investigated the effects of body mass index, diabetes, metabolic syndrome, exercise, weight loss medication, or bariatric surgery on semen parameters, sperm quality, or fertility outcomes. This review suggests that obesity, diabetes, and metabolic syndrome have a negative impact on various parameters of male fertility, from semen quality to sperm deoxyribonucleic acid integrity. There is also mounting evidence that male obesity is correlated negatively with live births via both natural conception and assisted reproductive technologies. Lifestyle interventions, such as physical exercise, generally appear to improve male fertility markers; however, the type and intensity of exercise may play a crucial role. Pharmacologic treatments for weight loss, such as metformin and glucagon-like peptide 1 agonists, present a more complex picture, with studies suggesting both beneficial and detrimental effects on male reproductive health. Similarly, surgical interventions, such as gastric bypass surgery, show promise in improving hormonal imbalances but have mixed effects on semen parameters. Future research is needed to clarify these associations and inform clinical guidelines. In the interim, health practitioners should incorporate these insights into clinical practices, encouraging proactive lifestyle changes and providing targeted treatments to improve male reproductive health.

Analysis of semen parameters, and hormonal changes of FSH, LH, testosterone, and libido following bariatric surgery

Introduction

Although studies have shown that bariatric surgery can have a positive effect on the patient's sexual function, there are still disagreements and contradictions in this regard. The present study is aimed to evaluate semen parameters, hormonal changes of FSH, LH, testosterone, and libido following bariatric surgery.

Methods

The present research as a prospective study was performed on 20 male candidates for bariatric surgery referred to Golestan and Aria hospitals in Ahvaz in 2021. Semen parameters (volume, count, motility, and the percentage of sperm with normal morphology), hormonal profile (including FSH, LH test hormones), and sexual function were evaluated using the International Index of Erectile Function (IIEF-5) questionnaire before and 6 months after the surgery.

Results

The results of this study indicated that semen parameters did not change significantly 6 months after surgery in comparison with before the surgery (P < 0.05). After the operation, just the total level of testosterone increased significantly (2.23 nmol/L vs. 2.74, P = 0.009). However, LH and FSH levels did not change significantly six months after surgery (P = 0.858 and P = 0.287). The results indicated significant improvement in IIEF score after the operation (P = 0.011).

Conclusion

The findings of the present study indicated that the decrement of weight as a result of bariatric surgery had a favorable effect on the levels of serum testosterone and sexual performance, while semen parameters did not improve after surgery.

Dietary trends and the decline in male reproductive health

Over the twentieth century, male reproductive health has suffered a substantial decline, as evidenced by decreases in sperm counts and testosterone levels and increases in reproductive pathologies. At the same time, the prevalence of chronic diseases such as obesity, diabetes, and metabolic syndrome has risen dramatically. Metabolic and reproductive health are highly interconnected, suggesting that their respective trends are intertwined and, given the timeframe of such trends, environmental and not genetic factors are most likely to be the primary causes. Industrialization, which began in Europe in the mid-eighteenth century, has resulted in profound changes to our diet, lifestyle, and environment, many of which are causal factors in the rise in chronic diseases. Industrialization results in a nutrition transition from an agricultural unprocessed to a modern processed diet, incorporating increases in sugar, vegetable oils, ultra-processed foods, linoleic acid, trans-fats, and total energy. This dietary shift has incurred numerous adverse effects on metabolic and reproductive health, characterized by chronic inflammation, oxidative stress, and insulin resistance. Moreover, these effects appear to multiply across subsequent generations via epigenetic inheritance. Men's fertility is markedly affected by obesity and diabetes, with an increase in total energy via processed food intake arguably being the key factor driving the diabesity pandemic. In contrast, wholefoods rich in micronutrients and phytonutrients support male fertility and a healthy body weight. Therefore, men wanting to maximize their fertility should consider making positive dietary changes, such as replacing processed foods with unprocessed foods that support metabolic and reproductive health.

Obesity: A Doorway to a Molecular Path Leading to Infertility

The dramatic rise in obesity has recently made it a global health issue. About 1.9 billion were overweight, and 650 million global populations were obese in 2016. Obese women suffer longer conception time, lowered fertility rates, and greater rates of miscarriage. Obesity alters hormones such as adiponectin and leptin, affecting all levels within the hypothalamic-pituitary-gonadal axis. Advanced glycation end products (AGEs) and monocyte chemotactic protein-1 (MCP-1) are inflammatory cytokines that may play an important role in the pathophysiology of ovarian dysfunction in obesity. In obese males, there are altered sperm parameters, reduced testosterone, increased estradiol, hypogonadism, and epigenetic modifications transmitted to offspring. The focus of this article is on the possible adverse effects on reproductive health resulting from obesity and sheds light on different molecular pathways linking obesity with infertility in both female and male subjects. Electronic databases such as Google Scholar, Embase, Science Direct, PubMed, and Google Search Engine were utilized to find obesity and infertility-related papers. The search strategy is detailed in the method section. Even though multiple research work has shown that obesity impacts fertility in both male and female negatively, it is significant to perform extensive research on the molecular mechanisms that link obesity to infertility. This is to find therapeutics that may be developed aiming at these mechanisms to manage and prevent the negative effects of obesity on the reproductive system.

Infertility in Men: Advances towards a Comprehensive and Integrative Strategy for Precision Theranostics

Male infertility is an increasing and serious medical concern, though the mechanism remains poorly understood. Impaired male reproductive function affects approximately half of infertile couples worldwide. Multiple factors related to the environment, genetics, age, and comorbidities have been associated with impaired sperm function. Present-day clinicians rely primarily on standard semen analysis to diagnose male reproductive potential and develop treatment strategies. To address sperm quality assessment bias and enhance analysis accuracy, the World Health Organization (WHO) has recommended standardized sperm testing; however, conventional diagnostic and therapeutic options for male infertility, including physical examination and semen standard analysis, remain ineffective in relieving the associated social burden. Instead, assisted reproductive techniques are becoming the primary therapeutic approach. In the post-genomic era, multiomics technologies that deeply interrogate the genome, transcriptome, proteome, and/or the epigenome, even at single-cell level, besides the breakthroughs in robotic surgery, stem cell therapy, and big data, offer promises towards solving semen quality deterioration and male factor infertility. This review highlights the complex etiology of male infertility, especially the roles of lifestyle and environmental factors, and discusses advanced technologies/methodologies used in characterizing its pathophysiology. A comprehensive combination of these innovative approaches in a global and multi-centric setting and fulfilling the suitable ethical consent could ensure optimal reproductive and developmental outcomes. These combinatorial approaches should allow for the development of diagnostic markers, molecular stratification classes, and personalized treatment strategies. Since lifestyle choices and environmental factors influence male fertility, their integration in any comprehensive approach is required for safe, proactive, cost-effective, and noninvasive precision male infertility theranostics that are affordable, accessible, and facilitate couples realizing their procreation dream.

Bariatric Surgery Does Not Improve Semen Quality: Evidence from a Meta-analysis

The meta-analysis aimed to explore the possible relationship between bariatric surgery and semen quality. PubMed, EMBASE, and CENTRAL were searched from database inception through October 28, 2021. Articles were eligible for inclusion if they evaluated the impact pre- and post-bariatric surgery on semen parameters. A total of 9 studies with 218 patients were found. The mean preoperative age distribution of the patients included centralized from 18 to 50 years, and the mean pre-op BMI ranged from 36.7 to 70.5 kg/m². The follow-up period ranged from 6 to 24 months. The results revealed that bariatric surgery had no significant effect on sperm volume, concentration, total count, morphology, total motility, progressive motility, viability, semen pH, and semen leukocytes. Bariatric surgery does not improve semen quality in obese males.

Decrease in Sperm Count After Bariatric Surgery: Case Reports

Morbid obesity is associated with a large number of complications, including infertility; weight loss can help to improve fertility and increase the number of sperm in males. However, two of our patients developed azoospermia after bariatric surgery for weight reduction.

A 30-year-old male presented to the outpatient department (OPD) with a BMI of 81.2 kg/m² (258 kg) with no known co-morbidities. The patient had a normal sex life and one child. After bariatric surgery, he noticed a change in the consistency of his semen and azoospermia. In the second case, a 48-year-old man presented to the OPD with a BMI of 52 kg/m² (189 kg) with no known co-morbidities. He had three children. He underwent bariatric surgery for weight loss and, after one year, he developed azoospermia.

Bariatric surgery is a lifesaving procedure for morbidly obese patients and helps in restoring normal daily activities. This weight reduction surgery helps in decreasing blood pressure, increasing glycemic control and improving sexual activity. However, bariatric surgery may be followed by a further decline in semen parameters, resulting in azoospermia and severe oligoasthenoteratozoospermia. This is caused by the combined effects of two different processes: 1) the subduing of the negative effects of obesity, and 2) a deficiency of nutrients along with the release of some harmful substances. Bariatric surgery patients should be informed about the risk of complications and about the possibility for cryopreservation of sperm.

In rare cases, bariatric surgery can result in a decrease in sperm count and infertility in males.

Secondary azoospermia after sleeve gastrectomy: a case report

OBJECTIVE

To report the first case of secondary azoospermia after sleeve gastrectomy.

DESIGN

Case report.

SETTING

Academic male infertility clinic.

PATIENTS

A 33-year-old man with secondary azoospermia and primary testicular failure with testosterone deficiency after laparoscopic sleeve gastrectomy.

INTERVENTIONS

Hormonal therapy with anastrozole for 10 months and diagnostic testicular biopsy.

MAIN OUTCOME MEASURES

Semen analyses and testicular histopathology.

RESULTS

Non-obstructive azoospermia persisted at 20 months after surgery despite hormonal therapy with anastrozole. Testicular histopathology revealed the presence of Sertoli cells only.

CONCLUSIONS

Although further research is need to determine the relationship between sleeve gastrectomy and secondary infertility, men should be informed of the potentially deleterious effects of this surgery on semen parameters.

Male infertility due to testicular disorders

CONTEXT

Male infertility is defined as the inability to conceive following 1 year of regular unprotected intercourse. It is the causative factor in 50% of couples and a leading indication for assisted reproductive techniques (ART). Testicular failure is the most common cause of male infertility, yet the least studied to date.

EVIDENCE ACQUISITION

The review is an evidence-based summary of male infertility due to testicular failure with a focus on etiology, clinical assessment, and current management approaches. PubMed-searched articles and relevant clinical guidelines were reviewed in detail.

EVIDENCE SYNTHESIS/RESULTS

Spermatogenesis is under multiple levels of regulation and novel molecular diagnostic tests of sperm function (reactive oxidative species and DNA fragmentation) have since been developed, and albeit currently remain as research tools. Several genetic, environmental, and lifestyle factors provoking testicular failure have been elucidated during the last decade; nevertheless, 40% of cases are idiopathic, with novel monogenic genes linked in the etiopathogenesis. Microsurgical testicular sperm extraction (micro-TESE) and hormonal stimulation with gonadotropins, selective estrogen receptor modulators, and aromatase inhibitors are recently developed therapeutic approaches for men with the most severe form of testicular failure, nonobstructive azoospermia. However, high-quality clinical trials data is currently lacking.

CONCLUSIONS

Male infertility due to testicular failure has traditionally been viewed as unmodifiable. In the absence of effective pharmacological therapies, delivery of lifestyle advice is a potentially important treatment option. Future research efforts are needed to determine unidentified factors causative in "idiopathic" male infertility and long-term follow-up studies of babies conceived through ART.

Obesity and male infertility: Mechanisms and management

Obesity is considered a global health problem affecting more than a third of the population. Complications of obesity include cardiovascular diseases, type 2 diabetes mellitus, malignancy (including prostatic cancer), neurodegeneration and accelerated ageing. In males, these further include erectile dysfunction, poor semen quality and subclinical prostatitis. Although poorly understood, important mediators of obesity that may influence the male reproductive system include hyperinsulinemia, hyperleptinemia, chronic inflammation and oxidative stress. Obesity is known to disrupt male fertility and the reproduction potential, particularly through alteration in the hypothalamic-pituitary-gonadal axis, disruption of testicular steroidogenesis and metabolic dysregulation, including insulin, cytokines and adipokines. Importantly, obesity and its underlying mediators result in a negative impact on semen parameters, including sperm concentration, motility, viability and normal morphology. Moreover, obesity inhibits chromatin condensation, DNA fragmentation, increases apoptosis and epigenetic changes that can be transferred to the offspring. This review discusses the impact of obesity on the male reproductive system and fertility, including associated mechanisms. Furthermore, weight management strategies, lifestyle changes, prescription medication, and complementary and alternative medicine in the management of obesity-induced subfertility is discussed.

Male Obesity Associated Gonadal Dysfunction and the Role of Bariatric Surgery

Obesity is an ever growing pandemic and a prevalent problem among men of reproductive age that can both cause and exacerbate male-factor infertility by means of endocrine abnormalities, associated comorbidities, and direct effects on the precision and throughput of spermatogenesis. Robust epidemiologic, clinical, genetic, epigenetic, and preclinical data support these findings. Clinical studies on the impact of medically induced weight loss on serum testosterone concentrations and spermatogenesis is promising but may show differential and unsustainable results. In contrast, literature has demonstrated that weight loss after bariatric surgery is correlated with an increase in serum testosterone concentrations that is superior than that obtained with only lifestyle modifications, supporting a further metabolic benefit from surgery that may be specific to the male reproductive system. The data on sperm and semen parameters is controversial to date. Emerging evidence in the burgeoning field of genetics and epigenetics has demonstrated that paternal obesity can affect offspring metabolic and reproductive phenotypes by means of epigenetic reprogramming of spermatogonial stem cells. Understanding the impact of this reprogramming is critical to a comprehensive view of the impact of obesity on subsequent generations. Furthermore, conveying the potential impact of these lifestyle changes on future progeny can serve as a powerful tool for obese men to modify their behavior. Healthcare professionals treating male infertility and obesity need to adapt their practice to assimilate these new findings to better counsel men about the importance of paternal preconception health and the impact of novel non-medical therapeutic interventions. Herein, we summarize the pathophysiology of obesity on the male reproductive system and emerging evidence regarding the potential role of bariatric surgery as treatment of male obesity-associated gonadal dysfunction.