Treatment of oligozoospermia with tamoxifen (open and controlled studies)

A systematic review and meta-analysis of the placebo effect on both semen quality and male infertility

INTRODUCTION

Placebo influence on such objective indicators, as sperm quality and infertility, has not been studied previously, but some studies report that placebo may distort even objective outcomes. The aim of current study is to assess the placebo effect on fertility in patients suffering from sperm abnormalities and/or infertility.

EVIDENCE ACQUISITION

We conducted a search of two databases (Scopus and MEDLINE) and identified placebo-controlled clinical trials which focused on sperm abnormalities and/or male infertility treatment. Primary outcomes included changes in semen parameters (volume, total count, sperm concentration in semen, progressive motility, morphology (normal cells)). Secondary outcomes included DNA fragmentation and change in pregnancy rate.

EVIDENCE SYNTHESIS

Seventy-seven articles published from 1983 to 2022 were included. Statistically significant changes were observed for the following values: total sperm count, mean change 0.16 (95% CI 0.05, 0.26); P=0.004, I2=75.1%; and progressive motility, mean change 0.13 (95% CI 0.02, 0.24); P=0.026, I2=84.9%. In contrast, placebo did not affect sperm concentration, sperm volume, sperm morphology or DNA fragmentation index. The publication bias for all the values measured with Egger's test and funnel plots was low.

CONCLUSIONS

The current meta-analysis indicated a statistically significant increase of total sperm count and progressive motility in the placebo group. In contrast, placebo did not affect sperm concentration, sperm volume, sperm morphology and DNA fragmentation index. These findings should be considered while planning or analyzing placebo-controlled clinical trials.

[Medical treatments for male infertility]

BACKGROUND

Treatments to stimulate spermatogenesis and antioxidant food supplements are often offered to infertile patients either before sperm extraction surgery to improve results, or as part of medically assisted reproduction or spontaneous fertility to increase the likelihood of a live birth.

METHODS

A bibliographic search limited to English-language literature on men published before 5/2023 was carried out, including clinical trials, literature reviews and meta-analyses on spermatogenesis-stimulating molecules and antioxidant treatments.

RESULTS

Several medical treatments seem capable of improving male fertility: they act mainly by stimulating spermatogenesis through hormones, or by reducing the effects of oxidative stress. With regard to oligoasthenozoospermia, the literature shows that certain hormonal treatments stimulating spermatogenesis are useful. In the case of non-obstructive azoospermia, the value of treatment depends on the patient's FSH and testosterone levels. AOX supplementation appears to improve certain spermogram parameters and have an impact on pregnancy and live birth rates.

CONCLUSION

This review should help urologists gain a better understanding of the various medical treatments and enable them to define an appropriate therapeutic strategy, tailored to the patient and the couple, in order to obtain the best results.

Effects of the selective estrogen receptor modulators for the treatment of male infertility: a systematic review and meta-analysis

Background: Selective estrogen receptor modulators (SERMs) represent a poorly investigated class of drugs for the treatment of male infertility. The aim of this study was to assess the effects of SERMs on conventional sperm parameters, serum gonadotropin and testosterone levels, and pregnancy rate in patients with idiopathic infertility. Methods: The authors performed a comprehensive systematic review with meta-analysis of all available controlled and not-controlled studies of the literature reporting sperm conventional parameters, gonadotropin and testosterone levels, and/or the pregnancy rate following SERM administration in normogonadotropic patients with idiopathic oligozoospermia. Results: From the 418 papers retrieved, 16 controlled and not-controlled trials were lastly included. SERM administration increased significantly sperm concentration, total sperm count, and serum luteinizing hormone, follicle-stimulating hormone, and total testosterone levels compared with baseline values. In contrast, SERMs did not have any significant effect on sperm concentration and progressive and total motility, but improved total sperm count, sperm morphology, and increased the pregnancy rate compared to the control group, which included studies done with placebo or other treatments. Conclusions: The results of this meta-analysis suggest that SERMs may be effective in the treatment of infertile patients with idiopathic infertility. However, the paucity of data does not allow to draw a definitive conclusion.

Reproductive sequelae of diabetes in male patients

Diabetes mellitus (DM) is an increasingly prevalent public health concern. A recent study projected the number of people worldwide with DM to increase from 171 million in 2000 to 366 million in 2030. Although DM is a systemic disease that often leads to end-organ dysfunction of multiple body systems, the effects of the condition on male fertility are often not fully appreciated. DM is associated with multiple risk factors for reduced male fertility potential, including erectile dysfunction, various manifestations of ejaculatory dysfunction, and hypogonadism.

Oral tamoxifen citrate treatment is more effective in normogonadotropic patients who have follicle-stimulating hormone levels within the lower half of normal

OBJECTIVE

To identify a subgroup of normogonadotropic men who may benefit relatively more from TC (tamoxifen citrate; a widely prescribed drug for male infertility) among those with FSH (follicle-stimulating hormone) values in the lower or higher halves of the normal range.

PATIENTS AND METHODS

In this retrospective study, 120 normogonadotropic infertile men with idiopathic oligozoospermia were included. All patients received 20 mg TC daily as a single dose for 6 months, and semen analysis and hormone levels were analyzed after 6 months, with the values being compared with those before treatment.

RESULTS

The FSH, luteinizing hormone and testosterone levels were significantly increased after the use of oral TC 20 mg daily. The sperm counts of the patients in the lower initial FSH group had a significantly higher increase in sperm count and concentration compared to the relatively higher FSH group.

CONCLUSION

This study revealed that initial FSH values can be used as a marker to estimate the probability that a patient will benefit from oral TC therapy. Patients in the lower FSH group had statistically higher chances of having higher sperm counts after treatment, and it is rational to advise these patients to receive 6 months of oral TC therapy. However, before drawing firm conclusions from this retrospective study, these results should be confirmed with double-blind, placebo-controlled, randomized trials.

Endocrine manipulation in male infertility

Endocrine therapy for male infertility is broadly categorized as specific or nonspecific therapy. Although uncommon, primary endocrine diagnoses in infertile men are amenable to targeted therapy. The efficacy of empiric endocrine therapy for idiopathic male infertility, however, has not been demonstrated conclusively by clinical trials. With better understanding of the underlying pathophysiology of idiopathic male infertility, careful evaluation of endocrine therapy in well-selected treatment groups and well-designed randomized, controlled trials is warranted. Although empiric endocrine therapy for idiopathic male infertility has been largely replaced by assisted reproductive techniques, both treatment modalities could play a role, perhaps as combination therapy.

Effect of tamoxifen treatment on the semen quality and fertility of the male rat

OBJECTIVES

To determine the effects of tamoxifen treatment on the seminal quality and fertility of the male Wistar rat.

DESIGN

Experimental prospective study.

SETTING

Animal research and university laboratory facility.

SUBJECT(S)

Seventy-five-day-old male and female Wistar rats.

INTERVENTION(S)

Sperm quality parameters were assayed in seminal and epididymal sperm samples in control and treated rats at a dose of 0.4 mg tamoxifen/kg per day. In addition, mating studies were performed, and different fertility parameters were assayed.

RESULT(S)

Tamoxifen treatment significantly decreased sperm concentration and motility in seminal and epididymal sperm. Sperm viability and hypo-osmotic swelling test results were shown not to be altered. The copulatory plug was absent or severely impaired in tamoxifen-treated males. When mating experiments were performed, a significant decrease in the fertility index and increased percentages of preimplantation and postimplantation embryo loss were also observed.

CONCLUSION(S)

Tamoxifen treatment significantly altered sperm quality in seminal and epididymal sperm. These alterations were present in testis and epididymis, and additional negative effects on the sexual accessory glands were observed. Finally, these alterations were capable of seriously compromising fertility ability of these male rats.

A new look at the medical management of infertility

Effective therapies are available for the treatment of infertility owing to specific causes. Most hormonal imbalances can be readily identified and successfully treated. The treatment of men with unexplained idiopathic infertility remains difficult. The availability of a multitude of agents ranging from hormones to nutritional supplements emphasizes the fact that none are consistently effective. There is no good way to predict which patients will respond to a specific treatment. Idiopathic infertility may result from multiple discrete defects in sperm generation and maturation that are as yet unidentified. A better understanding of these defects will yield more effective treatment options and appropriate triage of patients to specific therapeutic regimens. Assisted reproductive techniques remain an option for patients with idiopathic male infertility; however, they are expensive and treat the female partner for a male problem. Multiple gestations and other complications are not infrequent. Initial management should be directed at improving the quality of semen to facilitate natural conception. Specific abnormalities should be corrected. If empiric pharmacologic therapy is to be used, treatment should last at least 3 to 6 months to incorporate a full 74-day spermatogenic cycle. The infertile couple should be advised of the inconsistent response to therapy and the low conception rate that may follow when compared with the results of ART. When empiric therapy is decided upon, antiestrogens may be used and are effective in a subset of patients. The authors prefer to use clomiphene citrate, 25 mg per day. The dose may be increased to 50 or 75 mg to raise testosterone levels to the upper normal range. Lack of a significant improvement in semen parameters or of a pregnancy after a 3- to 6-month treatment period may be an indication to proceed with ART.

Present and future therapeutic strategies for idiopathic oligozoospermia

The effectiveness of medical treatment for idiopathic oligozoospermia (IO) has been at best doubtful until now and a logical consequence of this unsatisfactory situation has been the partial displacement of this approach by assisted reproduction techniques. This state of affairs has resulted from insufficient investigation, inappropriately designed clinical trials and consistent disregard for the principles of evidence-based medicine. Protocol-related shortcomings and wrong interpretation of the data available have also been some of the all too frequent problems encountered in this therapeutic approach. In this rather misty situation, it appears that, of the therapeutic agents used so far, follicle stimulating hormone (FSH) (mainly FSH-secretagogues) may exert some beneficial effects on a number of biological endpoints related to spermatogenesis and sperm maturation. The short and medium term prospects of medical treatment for IO rest mainly with improvement of investigative procedures to a higher degree of sophistication, with emphasis placed on identifying the causes rather than the results of dysfunction so that a better selection of candidates can be made. Moreover, the introduction of prognostic indices for evaluation of the beneficial effects of a therapeutic agent may be of paramount importance. Finally, a better assessment of the preparations available and, possibly, the introduction of new more specific agents may also be an important step forward in this field. This type of large-scale effort should not be left to individual investigators or special centres working independently, but it may come under the auspices of a central regulating agency so that undisputed results from large, multicentre and uniform studies might be obtained, if medical treatment is to remain a good option. In this context, it may also be emphasized that andrology's main task should always be to treat the male with the problem rather than his healthy female partner, whenever this is possible.

Clomiphene or tamoxifen for idiopathic oligo/asthenospermia

BACKGROUND

Oligo-astheno-teratospermia (sperm of low concentration, reduced motility and increased abnormal morphology) of unknown cause is common and the need for treatment is felt by patients and doctors alike. As a result, a variety of empirical, non-specific treatments have been used in an attempt to improve semen characteristics and fertility. The administration of anti-oestrogens is a common treatment because anti oestrogens interfere with the normal negative feedback of sex steroids at hypothalamic and pituitary levels in order to increase endogenous gonadotropin-releasing hormone secretion from the hypothalamus and FSH and LH secretion directly from the pituitary. In turn, FSH and LH stimulate Leydig cells in the testes, and this has been claimed to lead to increased local testosterone production, thereby boosting spermatogenesis with a possible improvement in fertility. There may also be a direct effect of anti-oestrogens on testicular spermatogenesis or steroidogenesis. This review considers the available evidence of the effect of both Clomiphene citrate and tamoxifen, both of which have a predominant anti-oestrogenic effect, for idiopathic oligo and/or asthenospermia.

OBJECTIVES

The objective was to assess the effects of treating subfertile men with anti-oestrogens (clomiphene or tamoxifen) on pregnancy rates among couples where subfertility has been attributed to idiopathic oligo- and/or asthenospermia.

SEARCH STRATEGY

The Cochrane Subfertility Review Group specialised register of controlled trials was searched".

SELECTION CRITERIA

Randomised trials of anti-oestrogen therapy for 3 months or more compared to placebo or no placebo for subfertile males among couples where subfertility is attributed to male factor.

DATA COLLECTION AND ANALYSIS

Data were extracted independently by two reviewers. Any differences were resolved with a third reviewer.

MAIN RESULTS

Ten studies involving 738 men were included. Five of the trials did not specify method of randomisation. Anti-oestrogens had a positive effect on endocrinal outcomes, such as serum testosterone levels. In trials with secure randomisation there was no difference in the pregnancy rate between the anti-oestrogen groups and the control groups (odds ratio 1.26, 95% confidence interval 0.99 to 1.56). The overall pregnancy rate for these five trials was 15.4% compared to the spontaneous rate of 12.5% in the control groups. These odds increased to 1.56 (95% confidence interval 0.99 to 2.19) when all 10 trials were included, but this result is likely to be artificially inflated.

REVIEWER'S CONCLUSIONS

Anti-oestrogens appear to have a beneficial effect on endocrinal outcomes, but there is not enough evidence to evaluate the use of anti-oestrogens for increasing the fertility of males with idiopathic oligo-asthenospermia.

Androgens versus placebo or no treatment for idiopathic oligo/asthenospermia

BACKGROUND

Oligo-astheno-teratospermia (sperm of low concentration, reduced motility and increased abnormal morphology) of unknown cause is common and the need for treatment is felt by patients and doctors alike. As a result, a variety of empirical, non-specific treatments have been used in an attempt to improve semen characteristics and fertility. Androgens have been suggested as a treatment because its binding proteins maintain a maintain a high intratesticular level testosterone essential for spermatogenesis and because the epididymis and seminal vesicles affect the seminal constitution and sperm motility and are also androgen-dependent. However exogenous testosterone was found to exert negative feedback on the pituitary-gonadal axis and thereby to suppress FSH and LH secretion. Spermatogenesis was thus adversely affected. Nevertheless androgens are used for the treatment of male infertility either for a putative direct "stimulatory" or "rebound" therapy. The stimulatory androgens used are mesterolone and testosterone undecanoate which, it is postulated, in a form and dosage that does not influence pituitary gonadotrophin secretion, either have a direct stimulatory effect on spermatogenesis or influence sperm transport and maturation though an effect on the epididymis, ductus deferens and seminal vesicles. Other androgens have been used to produce a rebound effect. These androgens are administered to suppress gonadotrophin secretion and spermatogenesis. After androgen therapy is discontinued there is a surge of FSH and LH and spermatogenesis is recommenced. Because of their different proposed mechanisms of action, stimulatory and rebound androgen therapy are analysed separately in the comparisons. This review considers the available evidence of the effect of androgens for idiopathic oligo and/or asthenospermia.

OBJECTIVES

The objective of this review was to assess the effect of androgen treatment of men among couples where failure to conceive has been attributed to idiopathic oligo- and/or asthenospermia.

SEARCH STRATEGY

The Cochrane Subfertility Review Group specialised register of controlled trials was searched".

SELECTION CRITERIA

Randomised trials of mesterolone or testosterone undecanoate versus placebo or no treatment (stimulatory therapy), or testosterone enanthate or testosterone undecanoate versus placebo or no treatment (rebound therapy) in couples where subfertility is attributed to male factor.

DATA COLLECTION AND ANALYSIS

Eligibility and trial quality were assessed.

MAIN RESULTS

Eleven trials involving 930 patients were included. For stimulatory therapy, androgens had little effect on endocrinal outcomes and sperm parameters. The rate of pregnancy after androgens with stimulatory effect compared to no treatment or placebo was also similar (odds ratio 1.10, 95% confidence interval 0.75 to 1.61). In rebound therapy, no difference was found in sperm parameters. The pregnancy rate after androgens with rebound effect also showed no difference compared to no treatment or placebo (odds ratio 1.60, 95% confidence interval 0.42 to 6.16). Adverse effects such as headaches and exanthema were reported.

REVIEWER'S CONCLUSIONS

There is not enough evidence to evaluate the use of androgens for male subfertility. [This abstract has been prepared centrally.]

Bromocriptine for idiopathic oligo/asthenospermia

BACKGROUND

Oligo-astheno-teratospermia (sperm of low concentration, reduced motility and increased abnormal morphology)of unknown cause is common and the need for treatment is felt by patients and doctors alike. As a result, a variety of empirical, non-specific treatments have been used in an attempt to improve semen characteristics and fertility. Whilst bromocriptine treatment for reducing prolactin levels in hyperprolactinaemic males (as in females), and, in the treatment of hypogonadotropic hypogonadism with hyperprolactinaemia, is beneficial, it has also been used for oligospermic men in the absence of any endocrinopathy. Prolactin may play a direct role in spermatogenesis and hormone production. It has also been claimed that in oligospermic men with normal gonadotrophins mean prolactin levels are higher and that hyperprolactinaemia is more common compared to fertile men. It has been proposed that the administration of bromocriptine under these circumstances might counteract a prolactin-induced block on the action of gonadotrophins on the testicles and, subsequently, that the reduction in prolactin levels might lead to an improvement in semen parameters and fertility. Although it is not licensed for use in male infertility, bromocriptine has been used for normogonadotrophic individuals with oligospermia and normal or sligthly elevated prolactin levels. This review considers the available evidence of the effect of bromocriptine therapy for normoprolactinaemic males with idiopathic oligo and/or asthenospermia.

OBJECTIVES

The objective of this review was to assess the effects of bromocriptine on pregnancy rates among couples where subfertility has been attributed to idiopathic oligo- and/or asthenospermia.

SEARCH STRATEGY

The Cochrane Subfertility Review Group specialised register of controlled trials was searched".

SELECTION CRITERIA

Randomised trials of oral bromocriptine versus placebo or no treatment for couples with subfertility attributed to male factor.

DATA COLLECTION AND ANALYSIS

Data were extracted by one reviewer and any disagreements were resolved by discussion with other reviewers.

MAIN RESULTS

Four studies were included. The method of randomisation was not specified in any of the trials, which were all of crossover design. Compared with placebo, bromocriptine was associated with a significant reduction in serum prolactin levels (weighted mean difference -195.3 micro international units per litre, 95% confidence interval -276.5 to -114). No effects on sperm parameters were seen. There was also no effect on pregnancy rates observed between bromocriptine and placebo (0.70 odds ratio, 95% confidence interval 0.15 to 3.24).

REVIEWER'S CONCLUSIONS

Bromocriptine appears to reduce prolactin levels in subfertile men with normal gonadotrophic function. There is not enough evidence to show that bromocriptine is helpful in improving fertility.

Treatment of idiopathic and postvaricocelectomy oligozoospermia with oral tamoxifen citrate

OBJECTIVE

To identify a subgroup of men who may benefit from tamoxifen citrate (a widely prescribed drug for male infertility) among those with normogonadotrophic and hypergonadotrophic oligozoospermia, either idiopathic or after varicocelectomy.

PATIENTS AND METHODS

The study included infertile men with oligozoospermia, 136 referred to our outpatient clinic and 84 infertile after varicocelectomy. All patients received tamoxifen citrate (10 mg twice daily); semen analysis and hormone tests were repeated at the end of 3 and 6 months of treatment, the values being compared with those before treatment.

RESULTS

The levels of follicle-stimulating hormone, luteinizing hormone and testosterone increased in all groups receiving tamoxifen citrate. Normogonadotrophic patients had a significant increase in sperm count and concentration, while the slight increase detected in the hypergonadotrophic group was statistically insignificant.

CONCLUSION

In patients with normogonadotrophic oligozoospermia, tamoxifen citrate may be offered as a practical and economic alternative before using any assisted reproduction techniques. However, double-blind placebo-controlled trials are needed to confirm the findings of this preliminary study.

Infertility treatment: from cookery to science. The epidemiology of randomised controlled trials

OBJECTIVES

To review the epidemiology of published randomised controlled trials in infertility treatment over the last 25 years, with special emphasis on the number and quality of trials.

DESIGN

Computer literature review by MEDLINE backed up by a manual search of 41 journals. Each trial was classified according to the methodology described and quality criteria. The results were recorded in a computer database. Odds ratios (OR) and confidence intervals (CI) were calculated where the data were sufficient.

SUBJECTS

Couples suffering from primary or secondary infertility. The trials studied 33,761 patients overall.

SETTING

Institute of Epidemiology and Health Services Research, Leeds.

RESULTS

Five hundred and one randomised trials in male and female infertility treatment were identified between 1966 and 1990. Pregnancy was an outcome in 291 (58%) and these were the subject of detailed analysis. Two hundred and twenty-four (77%) and 67 (23%) 'pregnancy trials' were concerned, respectively, with female and male infertility. Four per cent of the trials were preceded by a sample size calculation, and the average sample size was 96 patients (range 5-933); 700 patients per group would be required to demonstrate plausible success rates for most treatments. The method of randomisation was unstated or pseudo-randomised in 206 (71%) of trials where pregnancy was an outcome. Only 29 (5.8%) of studies were multicentre. The method of confirmation of pregnancy was omitted for 70% of papers. Cross-over design was used in 103 (21%) of cases. Meta-analysis is possible for selected topics such as the use of anti-oestrogens in idiopathic oligospermia and unexplained female infertility. Eight cases of double reporting were identified.

CONCLUSIONS

Trials using randomised methodology were relatively few in comparison with other branches of medicine, although their use is important in the evaluation of treatment for infertility as treatment-independent pregnancy is common. It was encouraging to note that an exponential increase in the use of this methodology occurred during the last three years, especially in association with assisted conception techniques, and meta-analysis has become possible for selected topics. However, many trials suffer from an unrealistically small sample size, inappropriate use of cross-over design or pseudo-randomisation. The trend towards properly controlled studies should be encouraged but these studies should be of improved quality and organised on a multicentre or even international basis.

Tamoxifen treatment of idiopathic oligozoospermia: effect on hCG-induced testicular steroidogenesis and semen variables

The mechanisms behind the effects of antioestrogens on semen variables and steroidogenesis in patients with oligozoospermia are unknown. In order to further elucidate this, the steroidogenic response to acute hCG-stimulation was studied in patients with idiopathic oligozoospermia before and during treatment with the antioestrogen Tamoxifen. Also an evaluation of semen variables in these patients was performed. During Tamoxifen treatment serum concentrations of LH, FSH, progesterone, 17 alpha-progesterone, testosterone and oestradiol-17 beta increased whereas no effect was observed on prolactin and SHBG concentrations. A similar pattern in steroidogenic response to hCG-stimulation was observed before and during Tamoxifen treatment. Sperm density, motility and morphology all improved after Tamoxifen treatment. The present results are discussed in relation to the possible mechanism of action of antioestrogens in patients with oligozoospermia.

Selection of oligozoospermic men for tamoxifen treatment by an antiestrogen test

In a retrospective study 46 men with idiopathic normogonadotropic oligozoospermia were treated by 20 mg Tamoxifen daily for a period of 6 months. A significant improvement of sperm count, total sperm output, total and progressive motility as well as sperm morphology was observed. In 25 men before initiation of treatment a short-term antiestrogen test with daily 40 mg Tamoxifen for a period of one week was performed with assessment of serum levels of testosterone, LH and FSH before and afterwards. Considering hormonal response in those patients who showed a more than 50% increase of sperm count (responders), FSH levels after Tamoxifen administration were unaffected. In contrast, a significant increase of the FSH level was observed in the group of the non-responders. Serum testosterone and LH levels increased in both groups, but showed no obvious differences. A similar hormonal pattern was found in father's and nonfather's concerning the response of FSH after Tamoxifen administration. It is concluded that the response of FSH towards Tamoxifen may be of use to predict improvement of semen parameters and therefore seems to be suitable to select patients for Tamoxifen therapy.