Spermatid count as a predictor of response to FSH therapy

FSH Therapy in Male Factor Infertility: Evidence and Factors Which Might Predict the Response

Follicle-stimulating hormone (FSH) administration is applied in the management of subjects affected by hypogonadotropic hypogonadism. Whilst this application is widely recognized and established alone or in combination with human chorionic gonadotropin (hCG), a similar strategy is empirically advocated in idiopathic male factor infertility (MFI). In this setting, FSH therapy has been used to increase sperm quantity, quality, and pregnancy rate when FSH plasma concentrations are below 8 IU/L and when the seminal tract is not obstructed. In the literature, several studies suggested that giving FSH to patients with idiopathic MFI increases sperm count and motility, raising the overall pregnancy rate. However, this efficacy seems to be limited, and about 10-18 men should be treated to achieve one pregnancy. Thus, several papers suggest the need to move from a replacement approach to an overstimulating approach in the management of FSH therapy in idiopathic MFI. To this aim, it is imperative to determine some pharmacologic markers of FSH efficacy. Furthermore, it should be useful in clinical practice to distinguish, before starting the treatment, among patients who might respond or not to FSH treatment. Indeed, previous studies suggest that infertile men who have normal levels of gonadotropins in plasma might not respond to FSH treatment and about 50% of patients might be defined as "non-responders". For these reasons, identifying predictive markers of FSH action in spermatogenesis and clinical markers of response to FSH treatment is a fascinating area of study that might lead to new developments with the aim of achieving personalization of the treatment of male infertility. From this perspective, seminal parameters (i.e., spermatid count), testicular cytology, genetic assessment, and miRNA or protein markers in the future might be used to create a tailored FSH therapy plan. The personalization of FSH treatment is mandatory to minimize side effects, to avoid lost time with ineffective treatments, and to improve the efficacy, predicting the most efficient dose and the duration of the treatment. This narrative review's objective is to discuss the role of the different putative factors which have been proposed to predict the response to FSH treatment in idiopathic infertile men.

Predictive role of 17α-hydroxy-progesterone serum levels of response to follicle-stimulating hormone in patients with abnormal sperm parameters

OBJECTIVES

To study the possible role of serum 17α-hydroxy-progesterone (17αOH-P) levels in predicting favorable responses to follicle-stimulating hormone (FSH) administration in patients with normal serum FSH levels and idiopathic abnormal sperm parameters.

DESIGN

Prospective cohort study.

SETTING

University-affiliated fertility center.

PATIENTS

Fifty patients with oligozoospermia, asthenozoospermia, and/or teratozoospermia and normal serum levels of gonadotropins and total testosterone (TT).

INTERVENTION

Treatment with exogenous FSH is administered subcutaneously at a dose of 150 IU 3 times a week for 3 consecutive months.

MAIN OUTCOME MEASURE(S)

Luteinizing hormone levels, FSH levels, TT levels, 17αOH-P levels, testicular volume, conventional sperm parameters, and seminal spermatid concentration were evaluated before and after therapy. To evaluate the predictive role of pretreatment serum 17αOH-P levels on FSH responsiveness, the doubling of sperm concentration at the end of the FSH administration was considered a positive outcome.

RESULTS

After therapy, patients showed a significant increase in sperm concentration, total sperm count (TSC), progressive motility, percentage of normal forms, FSH levels, TT levels, and testicular volume. There was a negative correlation between pretreatment 17αOH-P levels and the posttreatment increase in sperm concentration, TSC, progressive motility, and normal morphology, and a positive correlation with the posttreatment increase in spermatids. Predictive analysis showed that 17αOH-P levels (<1.18 ng/mL) foretold a doubling of sperm concentration with a sensitivity of 90.0% and a specificity of 73.3%, and of TSC with a sensitivity of 91.3% and a specificity of 81.48%.

CONCLUSION

The results of this study suggest that pretreatment serum levels of 17αOH-P, a marker of steroidogenic function, appear to be able to predict the success of subcutaneous administration of exogenous FSH in terms of spermatogenesis improvement. Receiver operating characteristic curves indicated that 17αOH-P levels (<1.18 ng/mL) predict a doubling of sperm concentration and TSC after exogenous FSH administration to patients with idiopathic abnormal sperm parameters and normal gonadotropin levels.

Sperm Concentration Improvement May Be a Parameter Predicting Efficacy of FSH Therapy of Male Idiopathic Infertility

Testis stimulation with follicle-stimulating hormone (FSH) is one of the empirical treatments proposed for male idiopathic infertility, although reliable markers to predict its efficacy are still lacking. This study aimed to identify parameters able to predict FSH efficacy in terms of pregnancy achievement. A real-world study was conducted, enrolling idiopathic infertile men treated with FSH 150IU three times weekly. Patients were treated until pregnancy achievement or for a maximum of two years and two visits were considered: V0 (baseline) and V1 (end of FSH treatment). Primary endpoints were the V1-V0 percentage change in sperm concentration, total sperm count, and total motile sperm number. In total, 48 pregnancies were recorded (27.7%) among 173 men (age 37.9 ± 6.2 years). All three endpoints increased after FSH administration, and only the V1-V0 percentage of sperm concentration significantly predicted pregnancy (p = 0.007). A V1-V0 sperm concentration of 30.8% predicted pregnancy, and the sperm concentration V1-V0 percentage (Y) required to obtain a pregnancy was predicted according to its baseline values (x): Y = 9.8433x2 - 203.67x + 958.29. A higher number of pregnancies was reached in men with baseline sperm concentration below 7.3 million/mL. Thus, the percentage of sperm concentration increasing after FSH administration could predict the treatment efficacy in terms of pregnancy. At the dosage used, the efficacy was significantly higher in patients with a starting sperm concentration < 7.3 mill/mL. Mathematical analyses identified a function able to predict the sperm concentration increase required to obtain a pregnancy in relation to the baseline sperm number.

Investigational follicle-stimulating hormone receptor agonists for male infertility therapy

INTRODUCTION

According to estimates by the World Health Organization, about 17.5% of the adult population - roughly 1 in 6 globally - experience infertility. The causes of male infertility remain poorly understood and have yet to be fully evaluated. Follicle-stimulating hormone (FSH) represents an available and useful therapeutic strategy for the treatment of idiopathic infertility.

AREAS COVERED

We provide here an overview of the molecular mechanisms by which FSH stimulates Sertoli cells and the schemes, dosages, and formulations of FSH most prescribed so far and reported in the literature. We also evaluated the possible predictor factors of the response to FSH administration and the indications of the latest guidelines on the use of FSH for the treatment of male infertility.

EXPERT OPINION

FSH therapy should be considered for infertile male patients with oligoasthenoteratozoospermia and normal serum FSH levels to quantitatively and qualitatively improve sperm parameters and pregnancy and birth rates. The grade of evidence is very low to low, due to the limited number of randomized controlled studies and patients available, the heterogeneity of the studies, and the limited effect size. To overcome these limitations, preclinical and clinical research is needed to evaluate the most effective dose and duration of FSH administration.

Follicle-stimulating hormone effectiveness in male idiopathic infertility: What happens in daily practice?

OBJECTIVES

To assess the effectiveness of follicle-stimulating hormone (FSH) administration in male idiopathic infertility in a clinical setting.

METHODS

A retrospective real-world study was carried out, including all consecutive FSH-treated infertile men attending the Andrology Unit of Modena (Italy) from June 2015 to May 2022. Medical history, physical and andrological examinations, hormonal and seminal parameters, therapeutic management and pregnancy data were collected. The primary endpoint was the number of pregnancies obtained after FSH administration, whereas semen parameters change was the secondary outcome.

RESULTS

A total of 194 of 362 (53.6%) infertile men, eligible according to the Italian Health System regulations, were treated with FSH (mean age 37.9 ± 6.1 years). Following FSH administration (mean therapy duration 9.1 ± 7.1 months), 43 pregnancies were recorded (27.6%), of which 22 occurred naturally and 21 after assisted reproduction. A significant increase in sperm concentration (9.9 ± 12.2 vs. 18.9 ± 38.9 million/mL, p = 0.045) was detected after treatment, together with a significant increase in normozoospermia (from 1.0% to 5.1%, p = .044) and a reduction in azoospermia rate (from 9.8% to 7%, p = 0.044). Dividing the cohort in FSH-responders and non-responders, in terms of pregnancy achieved, higher sperm concentrations (15.7 ± 26.6 vs. 22.2 ± 25.7 million/mL, p = 0.033) and progressive sperm motility (18.0 ± 18.2 vs. 27.3 ± 11.3, p = 0.044) were found in pregnancy group.

CONCLUSION

Our experience suggests that FSH, empirically administered to men with idiopathic infertility, leads to pregnancy in one out of four patients and increases sperm concentration. Although the expected limits because of a real-world data study, the number of FSH-treated patients required to achieve one pregnancy seems to be lower in clinical setting if compared to previously published data.

Male infertility and gonadotropin treatment: What can we learn from real-world data?

Gonadotropin therapy to treat specific male infertility disorders associated with hypogonadotropic hypogonadism is evidence-based and effective in restoring spermatogenesis and fertility. In contrast, its use to improve fertility in men with idiopathic oligozoospermia or nonobstructive azoospermia remains controversial, despite being widely practiced. The existence of two major inter-related pathways for spermatogenesis, including FSH and intratesticular testosterone, provides a rationale for empiric hormone stimulation therapy in both eugonadal and hypogonadal males with idiopathic oligozoospermia or nonobstructive azoospermia. Real-world data (RWD) on gonadotropin stimulating for these patient subsets, mainly using human chorionic gonadotropin and follicle-stimulating hormone, accumulated gradually, showing a positive therapeutic effect in some patients, translated by increased sperm production, sperm quality, and sperm retrieval rates. Although more evidence is needed, current insights from RWD research indicate that selected male infertility patients might be managed more effectively using gonadotropin therapy, with potential gains for all parties involved.

Diagnostic and therapeutic workup of male infertility: results from a Delphi consensus panel

Male factor infertility (MFI) is a rising issue worldwide with significant socioeconomic costs and negative psychological consequences for the couple. Current guidelines provide recommendations for its diagnosis and treatment but several gaps in the management of MFI are encountered in clinical practice due to the lack of available evidence in published literature. Uncertainty in the management of MFI cases leads to a high degree of variability in therapeutic approaches. We planned a Delphi consensus method to provide insights and help bridge the gaps that separate clinical guidelines from real-world practice. The Advisory Board collected 41 statements on debated topics in the management of MFI, each including multiple items designed as a 5-point Likert scale. The questionnaire was sent by e-mail to a panel of Italian experts for a first round of voting; members of the panel were later invited to a second round of voting, preceded by discussion of the "hot topics" identified in the first round. At both rounds of the Delphi consensus 68 experts participated to the voting process. After the first round 25 statements were identified as hot topics, and these underwent the second round of voting. Consensus was reached on many, but not all cases, leaving vagueness on few debated topics where decisions are unsupported by clinical studies or driven by controversial results. In conclusion, indications emerging from this large panel of experts may help guide the management of male factor infertility in clinical practice. Studies are needed to address unanswered questions left by cases for whom no consensus was reached.

FSH therapy for idiopathic male infertility: four schemes are better than one

OBJECTIVE

The aim of this article is to propose an algorithm that aids the clinician to choose the best therapeutic scheme of follicle-stimulating hormone (FSH) in the treatment of men with idiopathic infertility, based on testicular volume (TV) and serum total testosterone concentrations; highlighting the potential role of additional therapy with hCG in a sequential temporal scheme.

MATERIALS AND METHODS

We subdivided patients in four clinical groups: patients with normal TV and serum testosterone concentrations (A); patients with normal TV and reduced serum testosterone concentrations (B); patients with reduced TV and serum testosterone concentration (C); patient with low TV e normal serum testosterone concentrations (D). Then, we administered to each group a specific therapeutic scheme. Group A: treated with FSH alone for at least 3 months; group B: treated with hCG alone twice a week for 3 months and addition of FSH for poor responders (unmodified sperm parameters); group C: treated ab initio with FSH and hCG until the pregnancy was reached; group D: treated with FSH alone for 3 months and addition of hCG for moderate poor responders (increased TV but unmodified sperm parameters) or second cycle of FSH for 3 months for severe poor responders (unmodified TV and sperm parameters). After 6 months we evaluated the therapeutic response in term of sperm parameters normalization rate, spontaneous pregnancy rate, and sperm DNA fragmentation normalization rate.

RESULTS

40% of patients became normozoospermic after treatment, while 30% achieved spontaneous pregnancy. B was the group that best responded to treatment in terms of normalization of seminal parameters; while the highest spontaneous pregnancy rate was obtained from the D group. B group also obtained the highest sperm DNA fragmentation normalization rate.

CONCLUSIONS

To date, no reliable predictors of response to treatment with FSH exist, but TV and serum testosterone concentrations can help the clinician to choose the best therapeutic scheme for men with idiopathic infertility. The groups treated with a sequential temporal scheme (B and D groups) showed better clinical results compared with two groups treated with conventional schemes (A and C groups).

Follicle-Stimulating Hormone Treatment and Male Idiopathic Infertility: Effects on Sperm Parameters and Oxidative Stress Indices according to FSHR c. 2039 A/G and c. -29 G/A Genotypes

Scientific evidence shows that the administration of follicle-stimulating hormone (FSH) to infertile patients with normal serum FSH concentrations improves sperm parameters in oligozoospermic men. The aim of this study was to evaluate the effects of highly purified urofollitropin (hpFSH) on conventional and bio-functional sperm parameters and on oxidative stress indices in patients with idiopathic infertility. We also evaluated the response to hpFSH on these parameters in relationship to FSHR c. 2039 A/G and FSHR c. -29 G/A genotypes. A prospective longitudinal study was conducted on 42 patients with idiopathic male infertility, 23 of whom underwent to FSHR c. 2039 A/G and FSHR c. -29 G/A genotyping. Each patient was asked to collect two semen samples before and after administration of 150 IU hpFSH three times a week for 16 weeks. Patients were divided into responders or non-responders based on whether their total sperm count had at least doubled or was less than double at the end of treatment, respectively. Responders showed a significantly higher semen volume, sperm concentration, spermatids, and leukocytes. Non-responders had a significant decrease of the percentage of spermatozoa in early apoptosis after hpFSH administration. Oxidative stress indexes did not differ significantly after FSH administration in both groups. Conventional and bio-functional sperm parameters did not differ in patients with FSHR c. 2039 GG and AA genotypes, and FSHR c. -29 GG genotype both before and after FSH administration. The FSHR c. 2039 and FSHR -29 G/A genotypes and allelic distribution did not differ between responders and non-responders. FSH showed to be capable of ameliorating sperm parameters in about half patients treated, therefore it may be helpful in patients with idiopathic infertility.

Use of Biosimilar Follicle-Stimulating Hormone in Asthenozoospermic Infertile Patients: A Multicentric Study

There is increasing data in favour of follicle-stimulating hormone (FSH) therapy in patients with oligo-asthenozoospermia and normal-range gonadotropins in order to increase sperm count and above all sperm motility. Some studies showed an improvement in DNA fragmentation and spontaneous pregnancy. Recently, biosimilar FSH has been marketed with the same indications. We performed a retrospective multicentric case-control study involving 147 asthenozoospermic patients between 18 and 45 years of age. A total of 97 patients were treated with biosimilar FSH 150 UI three times a week for 3 months, while 50 control subjects received no treatment. Patients were evaluated at baseline and after 3 months with semen analysis including DNA fragmentation, testicular colour Doppler ultrasound, and blood tests. Spontaneous pregnancies were recorded during a further follow-up period of 6 months. Treated patients showed after treatment a statistically significant increase in sperm concentration, total sperm count, and total motile sperm, as well as improved progressive motility and non-progressive motility. DNA fragmentation showed a significant reduction. Conversely, in the control group, no significant change was found. Pregnancy rate was significantly higher in treated patients. These data suggest comparable efficacy of biosimilar FSH in the treatment of male infertility; however, larger studies are needed to confirm our results.

Effects of FSH on Sperm DNA Fragmentation: Review of Clinical Studies and Possible Mechanisms of Action

Sperm DNA fragmentation (sDF) is an important reproductive problem, associated to an increased time-to-pregnancy and a reduced success rate in natural and in vitro fertilization. sDF may virtually originate at any time of sperm's life: in the testis, in the epididymis, during transit in the ejaculatory ducts and even following ejaculation. Studies demonstrate that an apoptotic pathway, mainly occurring in the testis, and oxidative stress, likely acting in the male genital tract, are responsible for provoking the DNA strand breaks present in ejaculated spermatozoa. Although several pharmacological anti-oxidants tools have been used to reduce sDF, the efficacy of this type of therapies is questioned. Clearly, anti-apoptotic agents cannot be used because of the ubiquitous role of the apoptotic process in the body. A notable exception is represented by Follicle-stimulating hormone (FSH), which regulates testis development and function and has been demonstrated to exert anti-apoptotic actions on germ cells. Here, we review the existing clinical studies evaluating the effect of FSH administration on sDF and discuss the possible mechanisms through which the hormone may reduce sDF levels in infertile subjects. Although there is evidence for a beneficial effect of the hormone on sDF, further studies with clear and univocal patient inclusion criteria, including sDF cut-off levels and considering the use of a pharmacogenetic approach for patients selection are warranted to draw firm conclusions.

FSH treatment in infertile males candidate to assisted reproduction improved sperm DNA fragmentation and pregnancy rate

The purpose of this study is to evaluate whether follicle-stimulating hormone treatment improves sperm DNA parameters and pregnancy outcome in infertile male candidates to in-vitro fertilization.Observational study in 166 infertile male partners of couples undergoing in-vitro fertilization. Eighty-four patients were receiving follicle-stimulating hormone treatment (cases) and 82 refused treatment (controls). Semen parameters, sexual hormones, and sperm nucleus (fluorescence in-situ hybridization, acridine orange, TUNEL, and γH2AX) were evaluated at baseline (T0) and after 3 months (T1), when all subjects underwent assisted reproduction techniques. Statistical analysis was performed by analysis of variance.Compared to baseline, cases showed significant improvements in seminal parameters and DNA fragmentation indexes after follicle-stimulating hormone therapy (all P < 0.05), whereas no changes were observed in controls. Within cases, follicle-stimulating hormone treatment allowed to perform intrauterine insemination in 35 patients with a pregnancy rate of 23.2 %. Intracytoplasmic sperm injection was performed in all controls and in 49 patients from cases, with pregnancy rates of 23.2 and 40.8 %, respectively (P < 0.05). After 3 months (T0 vs. T1) of follicle-stimulating hormone therapy, cases with positive outcome had reduced DNA fragmentation index and lower double strand breaks (P < 0.05 and P < 0.001 vs. negative outcome, respectively).In this observational study, we showed that follicle-stimulating hormone treatment improves sperm DNA fragmentation, which in turn leads to increased pregnancy rates in infertile males undergoing in-vitro fertilization. In particular, double strand breaks (measured with γH2AX test) emerged as the most sensible parameter to follicle-stimulating hormone treatment in predicting reproductive outcome.

Testicular Stem Cells Express Follicle-Stimulating Hormone Receptors and Are Directly Modulated by FSH

Testicular spermatogonial stem cells (SSCs) are a heterogeneous population of stem cells, and definitive marker for the most primitive subset that undergoes asymmetric cell division remains to be identified. A novel subpopulation of pluripotent, very small embryonic-like stem cells (VSELs) has been reported in both human and mouse testes. Follicle-stimulating hormone (FSH) receptors (FSHRs) are expressed on Sertoli cells in testis and on granulosa cells in ovary, but recently FSHRs are reported on VSELs in ovaries, bone marrow, and cord blood. The present study was aimed to investigate whether FSHRs are also expressed on testicular stem cells (VSELs and SSCs) and their possible modulation by FSH using intact and chemoablated (25 mg/kg busulfan) mice. Chemoablated testis was a better model to study stem cell biology since quiescent stem cells survive along with the Sertoli cells in the tubules. Proliferating cell nuclear antigen-positive, small-sized cells presumed to be VSELs were clearly visualized, and flow cytometry analysis revealed an increase in LIN^-/CD45^-/SCA-1⁺ VSELs from 0.045±0.008% to 0.1±0.03% of total cells in chemoablated testis after FSH treatment. Very small embryonic-like stem cells expressing nuclear octamer-binding transcription factor 4 (OCT-4) and SSCs with cytoplasmic OCT-4 were detected. Very small embryonic-like stem cells (Oct-4A, Sca-1, Nanog), SSCs (Oct-4), and proliferation (Pcna) specific transcripts were upregulated on FSH treatment. Stem cells expressed FSHR and were stimulated by FSH, and Fshr3 was the predominant transcript maximally modulated by FSH. Nuclear OCT-4 and SCA-1 (stem cell antigen 1) positive VSELs are the most primitive stem cells in testis, and FSH stimulates them to undergo asymmetric cell division including self-renewal and give rise to SSCs, which in turn proliferate rapidly and undergo clonal expansion and further differentiation.