Clomiphene citrate for male infertility: A systematic review and meta-analysis

Pharmacological non-hormonal treatment options for male infertility: a systematic review and network meta-analysis

BACKGROUND

Male factor infertility affect up to 50% of couples unable to conceive spontaneously. Several non-hormonal pharmacological treatments have been proposed to boost spermatogenesis and increase chances of conception in men with infertility. Still, no clear evidence exists on the most effective treatment strategy.

OBJECTIVE

We aimed to compare the effectiveness of non-hormonal pharmacological treatment options for men with infertility using a systematic review and network meta-analysis.

METHODS

We searched MEDLINE, EMBASE, and CENTRAL until October 2023 for randomised/quasi-randomised trials that evaluated any non-hormonal pharmacological treatment options for men with idiopathic semen abnormalities or those with hypogonadism. We performed pairwise and network meta-analyses using a random effect model. We assessed risk of bias, heterogeneity, and network inconsistency. We calculated the mean rank and the surface under the cumulative ranking curve (SUCRA) for each intervention the maximum likelihood to achieve each of reported outcomes. We reported primarily on sperm concentration and other important semen and biochemical outcomes using standardised mean difference (SMD) and 95% confidence-intervals(CI).

RESULTS

We included 14 randomised trials evaluating four treatments (Clomiphene citrate, Tamoxifen, Aromatase inhibitors, anti-oxidants) and their combinations in 1342 men. The overall quality of included trials was low. Sperm concentration improved with clomiphene compared to anti-oxidants (SMD 2.15, 95%CI 0.78-3.52), aromatase inhibitor (SMD 2.93, 95%CI 1.23-4.62), tamoxifen (SMD - 1.96, 95%CI -3.57; -0.36) but not compared to placebo (SMD - 1.53, 95%CI -3.52- 0.47). Clomiphene had the highest likelihood to achieve the maximum change in sperm concentration (SUCRA 97.4). All treatments showed similar effect for sperm motility, semen volume, and normal sperm morphology. FSH levels showed significant improvement with clomiphene vs.anti-oxidant (SMD 1.48, 95%CI 0.44-2.51) but not compared to placebo. The evidence networks for LH and testosterone suffered from significant inconsistency (p = 0.01) with similar trend of improvement with clomiphene compared to other treatments but not compared to placebo.

CONCLUSION

There is insufficient evidence to support the routine use of Clomiphene, tamoxifen, and aromatase inhibitors to optimise semen parameters in men with infertility. Future randomised trials are needed to confirm the efficacy of clomiphene in improving fertility outcomes in men.

PROSPERO

CRD42023430179.

Pharmacological management of testosterone deficiency in men current advances and future directions

INTRODUCTION

Testosterone deficiency (TD) is relatively common in aging men, affecting around 2% of the general population. Testosterone replacement therapy (TRT) represents the most common medical approach for subjects who are not interested in fathering.

AREAS COVERED

This review summarizes advances in TRT, including approved or non-approved pharmacological options to overcome TD. When possible, a meta-analytic approach was applied to minimize subjective and biased interpretations of the available data.

EXPERT OPINION

During the last decade, several new TRT formulations have been introduced on the market, including oral, transdermal, and parenteral formulations. Possible advantages and limitations have been discussed appropriately. Anti-estrogens, including selective estrogen modulators or aromatase inhibitors still represent further possible off-label options. However, long-term side effects on sexual function and bone parameters constitute major limitations. Glucagon-like peptide 1 analogues can be an alternative option in particular for massive obesity-associated TD. Weight loss obtained through lifestyle modifications including diet and physical exercise should be encouraged in all overweight and obese patients. A combination of TRT and lifestyle changes can be considered in those subjects in whom a reversal of the condition cannot be expected in a reasonable time frame.

Use of empirical medical therapies for idiopathic male infertility in Australia and New Zealand

OBJECTIVE

Idiopathic male infertility is common, yet there is no approved treatment. This study aimed to understand practice patterns towards empirical medical therapy (EMT) for idiopathic male infertility in Australia and New Zealand (NZ).

DESIGN

Clinical members of the Endocrine Society of Australia, Fertility Society of Australia & NZ, and Urological Society of Australia & NZ were invited to complete a survey. Questions included demographics, EMT practice habits, and thoughts regarding infertility case scenarios. Unadjusted group differences between specialists, those with and without additional training in male infertility, and frequency of managing it were evaluated.

RESULTS

Overall, 147 of 2340 members participated (6.3%); majority were endocrinologists and gynaecologists. Participants were experienced; 35% had completed additional training in male infertility and 36.2% reported they frequently manage male infertility. Gynaecologists were more likely to manage male infertility and attend education courses than endocrinologists and urologists. Beliefs about the effect of EMT on sperm concentration and pregnancy did not differ between speciality types. Many respondents considered all patient scenarios suitable for EMT. Of medications, hCG and clomiphene were selected most. Two respondents indicated they would use testosterone to treat male infertility.

CONCLUSIONS

This study demonstrates common use of EMT in Australia and NZ for idiopathic male infertility. The breadth of responses reflects a lack of consensus within the current literature, highlighting the need for further research to clarify their role in the management of idiopathic male infertility.

The effect of red blood cell disorders on male fertility and reproductive health

Male infertility is defined as a failure to conceive after 12 months of unprotected intercourse owing to suspected male reproductive factors. Non-malignant red blood cell disorders are systemic conditions that have been associated with male infertility with varying severity and strength of evidence. Hereditary haemoglobinopathies and bone marrow failure syndromes have been associated with hypothalamic-pituitary-gonadal axis dysfunction, hypogonadism, and abnormal sperm parameters. Bone marrow transplantation is a potential cure for these conditions, but exposes patients to potentially gonadotoxic chemotherapy and/or radiation that could further impair fertility. Iron imbalance might also reduce male fertility. Thus, disorders of hereditary iron overload can cause iron deposition in tissues that might result in hypogonadism and impaired spermatogenesis, whereas severe iron deficiency can propagate anaemias that decrease gonadotropin release and sperm counts. Reproductive urologists should be included in the comprehensive care of patients with red blood cell disorders, especially when gonadotoxic treatments are being considered, to ensure fertility concerns are appropriately evaluated and managed.

Diagnosis and treatment of hypogonadism in men seeking to preserve fertility - what are the options?

Male hypogonadism is a clinical syndrome that results in low testosterone levels and frequently leads to infertility. The syndrome occurs due to disruption at one or more levels of the hypothalamic-pituitary-gonadal axis. Testosterone replacement therapy (TRT) is the most common treatment utilised for male hypogonadism. However, long-acting forms of TRT leads to infertility and so is inappropriate for patients wishing to conceive. For patients who wish to remain fertile, nasal TRT, clomiphene citrate, exogenous gonadotropins, gonadotropin releasing hormone and aromatase inhibitors have been used as alternative treatment options with different degrees of success. A review of the literature was performed to identify the safety and efficacy of alternative treatment options. Gonadotropin releasing hormone can successfully induce spermatogenesis but is impractical to administer. Likewise, aromatase inhibitors have limited use due to inducing osteopenia. Nasal TRT may be a good treatment option for these patients, but its efficacy has so far only been demonstrated in small sample sizes. However, clomiphene citrate and exogenous gonadotropins are safe, offer good symptom control and can successfully induce fertility in hypogonadism patients.

Testing for clomiphene in keratinous matrices using LC-MS/MS in doping purpose: Is a single intake of clomiphene detectable in hair and nail clippings?

Clomiphene is a selective estrogen receptor modulator. It is indicated for the treatment of female infertility issues but in sport, it can be misused to stimulate endogenous testosterone secretion in men. Therefore, it has been prohibited at all times by the World Anti-doping Agency. The aim of this study was to get data to be able to interpret concentrations in athletes. A healthy volunteer (male, 62 years-old) ingested a single therapeutic dose of clomiphene (Clomid™, 50 mg). Strands of hair (blond, 4 cm) were collected one month after the ingestion. Body hair (beard, axillary, pubic and chest hair), and finger and toenails were collected over 4-5 months. A previous method was modified to identify and quantify clomiphene in keratinous matrices. 30 mg of specimen were sonicated and incubated in 1 mL of methanol, in presence of 200 pg of clomiphene-D5 (internal standard). After centrifugation and evaporation of the organic phase, the samples were analyzed using LC-MS/MS. Linearity was verified in hair and nail clippings between 1 and 500 pg/mg. The limits of detection and quantification were determined at 0.3 and 1 pg/mg respectively. The study demonstrated that clomiphene tested positive in all the analyzed specimens at 9 pg/mg in head hair, from 28 to 486 pg/mg (body hair) and from 4 to 57 pg/mg (nails). Clomiphene was identified for the first time in multiple keratinous matrices. This study demonstrated that a single oral therapeutic dose is detectable in keratinous matrices over a long period of time.

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 association of medications and supplements with human male reproductive health: a systematic review

Some medications used to treat comorbidities and conditions in reproductive-aged individuals could have a negative impact on fertility. This may occur through hormonal disruption, toxicity to germ cells and spermatozoa, functional impact on the sperm, teratogenicity potential, or ejaculatory abnormalities. Having knowledge of these potential interactions between medications and reproductive potential is important for clinicians to be aware of and guide the patient, along with their treating clinicians, to reproductively favorable alternatives when available. This review aims to summarize the state of the literature regarding medication interactions with human male reproduction using the Anatomical Therapeutic Chemical Classification System of medications.

Testing for clomiphene in keratinous matrices (hair and nail)

Clomiphene or clomifene is a selective estrogen receptor modulator used to treat female fertility in case of ovulatory dysfunction. In sport, clomiphene is prohibited at all times for use by athletes and is listed in the section S4.2 (hormone and metabolic modulators) by the World Anti-Doping Agency. Indeed, clomiphene can indirectly increase testosterone levels in the body and can mitigate some side effects of synthetic steroid abuse. Despite its prescription to millions of subjects, its detection in human hair or nail clippings has never been reported. The aim of this study was to develop a specific method to identify clomiphene in hair and nail clippings by liquid chromatography-quadrupole tandem mass spectrometry. The procedure was then applied in a case of challenged doping results. The method involves sonication/incubation for 1 h of 30 mg of pulverized material in 1 mL of methanol in the presence of 2 ng diazepam-d5 used as internal standard. The chromatographic separation was performed using a HSS C18 column with a 15 min gradient elution. After spiking blank hair and nail with the corresponding amounts of clomiphene, linearity was verified from 1 to 500 pg/mg (r2 = 0.9994 and 0.9995 for hair and nail, respectively). The limit of detection was estimated at 0.3 pg/mg for both matrices. No interference was noted from endogenous compounds, particularly steroids. Clomiphene was identified at 85 and 20 pg/mg in the pubic hair and the fingernail clippings, respectively, of a male athlete challenging an adverse analytical finding.

Early Pharmacologic Approaches to Avert Anabolic Steroid-induced Male Infertility: A Narrative Review

PURPOSE

To review the impact of testosterone and other androgenic-anabolic steroids (AASs) on male fertility, exploring potential drugs that can be used to preserve or restore male fertility upon AAS use or prior contact.

METHODS

A review was performed to provide a unifying clinical link between drugs used to preserve or restore male fertility (ie, clomiphene citrate, human chorionic gonadotropin, selective estrogen receptor modulators, recombinant luteinizing and follicle-stimulating hormones, and human menopausal gonadotrophin) in the context of AAS-induced infertility and related aspects.

FINDINGS

Human chorionic gonadotropin (125-500 IU every other day), clomiphene citrate (12.5-50 mg/d), recombinant luteinizing hormone (125-500 IU every other day), recombinant follicle-stimulating hormone (75-150 IU 1-3×/wk), and human menopausal gonadotrophin (75-150 IU 1-3×/wk) are promising early pharmacologic approaches to avert AAS-induced male infertility. Additionally, a full partner assessment is crucial to the success of a couple planning to have children. The partner's age and gynecopathies must be considered. Egg or sperm cryopreservation can also be alternatives for future fertility. Reinforcing AAS cessation is imperative to achieving better success in misusers.

IMPLICATIONS

The exponential increase in AAS misuse raises concerns about the impact on male fertility. This review suggests that gonadotropin analogs and selective androgen receptor modulators (clomiphene citrate) are viable approaches to early preserve or restore fertility in men on AAS use or with previous contact. However, proper standardization of doses and combinations is required and hence physicians should also be aware of patients' and partners' fertility.

Clomiphene Citrate in the Management of Infertility in Oligospermic Obese Men with Hypogonadism: Retrospective Pilot Study

Background and Objectives: Obesity is a significant risk factor for hypogonadism and infertility that is further associated with reduced semen quality. The aim of this study is to evaluate the effect of clomiphene citrate (CC), prescribed for treating infertility, on serum testosterone and semen parameters, particularly in oligospermic obese hypogonadal men. Materials and Methods: A retrospective analysis of data related to men (n = 53) who underwent CC treatment for infertility and hypogonadism (testosterone < 300 ng/dL) was performed. Patients with obesity (BMI ≥ 30 kg/m2) and sperm concentration ≤ 15 × 106/mL were included for analysis. Results: The overall results showed that, in oligospermic obese men (n = 31), treatment with CC significantly improved baseline sperm concentration (4.5 ± 6.8 × 106/mL vs. 11.4 ± 15.5 × 106/mL, p < 0.05) and motility (31.5% ± 21.5% vs. 42.6% ± 14.7%, p < 0.05). Furthermore, subsequent examination of oligospermic hypogonadal obese men treated with CC (n = 13) revealed substantial improvements in baseline serum testosterone levels (193.8 ± 59.3 ng/dL vs. 332.7 ± 114.8 ng/dL, p < 0.05) along with an increase in sperm concentration, total motility, and normal morphology. Conclusions: The results of this retrospective study suggest that CC treatment not only improves chances of fertility outcomes by substantially improving semen parameters but also increases total serum testosterone levels in oligospermic obese men without any supplemental and expensive testosterone replacement therapy.

Assessing the Prevalence of Low Testosterone and Elevated Follicle Stimulating Hormone Among Men Presenting for Fertility Evaluation Without Oligospermia

OBJECTIVE

To compare the prevalence of abnormal hormone parameters among men with and without oligospermia to determine the value of universal hormonal screening during initial fertility evaluation.

MATERIALS AND METHODS

We retrospectively evaluated men who underwent semen analysis and hormonal evaluation (morning testosterone [T] and follicle-stimulating hormone [FSH]) between January 2002 and May 2021. Sperm concentration was dichotomized at 15 million/mL according to World Health Organization (WHO) criteria. We compared median and interquartile range (IQR) T and FSH levels according to sperm concentration using Kruskal-Wallis test. Differences in prevalence of low testosterone (<300 ng/dL) and abnormal FSH (>7.6mIU/mL) were determined using chi-square test.

RESULTS

1164 men had a morning serum T. There was no difference in median T among men with normal vs abnormal sperm concentration (316 ng/dL, IQR 250-399 vs 316 ng/dL, IQR 253-419; P = .52). FSH was measured in 1261 men. Median FSH was higher among men with sperm concentration <15 million/mL (6.0IU/mL, IQR 3.9-10.7 vs 3.8IU/mL, IQR 2.7-5.7; P < .001). Among men with ≥15 million/mL concentration, 44.1% were found to have low T (P = .874) and 10.8% had an FSH ≥7.6 mIU/mL (P < .001). Among men with ≥15 million/mL sperm concentration who underwent both T and FSH evaluation, 43.6% had at least 1 hormonal abnormality.

CONCLUSION

Almost half of men with normal sperm concentration had low T. As low T may have long-term implications for both fertility and overall health, providers should consider universal T screening in men presenting for fertility evaluation.

Nuclear Estrogen Receptors in Prostate Cancer: From Genes to Function

Estrogens are almost ubiquitous steroid hormones that are essential for development, metabolism, and reproduction. They exert both genomic and non-genomic action through two nuclear receptors (ERα and ERβ), which are transcription factors with disregulated functions and/or expression in pathological processes. In the 1990s, the discovery of an additional membrane estrogen G-protein-coupled receptor augmented the complexity of this picture. Increasing evidence elucidating the specific molecular mechanisms of action and opposing effects of ERα and Erβ was reported in the context of prostate cancer treatment, where these issues are increasingly investigated. Although new approaches improved the efficacy of clinical therapies thanks to the development of new molecules targeting specifically estrogen receptors and used in combination with immunotherapy, more efforts are needed to overcome the main drawbacks, and resistance events will be a challenge in the coming years. This review summarizes the state-of-the-art on ERα and ERβ mechanisms of action in prostate cancer and promising future therapies.

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.

Potency Assays for Mesenchymal Stromal Cell Secretome-Based Products for Tissue Regeneration

Adult stem cells maintaining tissue homeostasis and regeneration are tightly regulated by their specific microenvironments or stem cell niches. The dysfunction of niche components may alter the activity of stem cells and ultimately lead to intractable chronic or acute disorders. To overcome this dysfunction, niche-targeting regenerative medicine treatments such as gene, cell, and tissue therapy are actively investigated. Here, multipotent mesenchymal stromal cells (MSCs), and particularly their secretomes, are of high interest due to their potency to recover and reactivate damaged or lost stem cell niches. However, a workflow for the development of MSC secretome-based products is not fully covered by regulatory authorities, and and this issue significantly complicates their clinical translation and has possibly been expressed in a huge number of failed clinical trials. One of the most critical issues in this regard relates to the development of potency assays. In this review, guidelines for biologicals and cell therapies are considered to be applied for the development of potency assays for the MSC secretome-based products that aim for tissue regeneration. Specific attention is paid to their possible effects on stem cell niches and to a spermatogonial stem cell niche in particular.