Pulsatile luteinizing hormone-releasing hormone treatment of male hypogonadotropic hypogonadism

The use of hormone stimulation in male infertility

Infertility affects 15% of couples worldwide and in approximately 50% of cases the cause is secondary to an abnormality of the sperm. However, treatment options for male infertility are limited and empirical use of hormone stimulation has been utilised. We review the contemporary data regarding the application of hormone stimulation to treat male infertility. There is strong evidence supporting the use of hormone stimulation in hypogonadotropic hypogonadism but there is inadequate evidence for all other indications.

Clinical Management of Congenital Hypogonadotropic Hypogonadism

The initiation and maintenance of reproductive capacity in humans is dependent on pulsatile secretion of the hypothalamic hormone GnRH. Congenital hypogonadotropic hypogonadism (CHH) is a rare disorder that results from the failure of the normal episodic GnRH secretion, leading to delayed puberty and infertility. CHH can be associated with an absent sense of smell, also termed Kallmann syndrome, or with other anomalies. CHH is characterized by rich genetic heterogeneity, with mutations in >30 genes identified to date acting either alone or in combination. CHH can be challenging to diagnose, particularly in early adolescence where the clinical picture mirrors that of constitutional delay of growth and puberty. Timely diagnosis and treatment will induce puberty, leading to improved sexual, bone, metabolic, and psychological health. In most cases, patients require lifelong treatment, yet a notable portion of male patients (∼10% to 20%) exhibit a spontaneous recovery of their reproductive function. Finally, fertility can be induced with pulsatile GnRH treatment or gonadotropin regimens in most patients. In summary, this review is a comprehensive synthesis of the current literature available regarding the diagnosis, patient management, and genetic foundations of CHH relative to normal reproductive development.

Gonadotrophin replacement for induction of fertility in hypogonadal men

Congenital hypogonadotrophic hypogonadism (CHH) is a rare form of infertility caused by deficient secretion or action of gonadotrophin-releasing hormone. There is no consensus regarding the optimal approach to fertility treatment in CHH men. In most cases, appropriate hormonal treatment with human chorionic gonadotrophin with or without follicle stimulating hormone will induce testicular development, spermatogenesis and fertility. Recent studies have examined sequential treatment with FSH pre-treatment to optimize fertility outcomes in severely affected CHH patients. This paper reviews historical and recent literature to summarize the current evidence on therapeutic approaches for CHH men seeking fertility.

Factors affecting spermatogenesis upon gonadotropin-replacement therapy: a meta-analytic study

A meta-analysis was performed to systematically analyse the results of gonadotropin and GnRH therapy in inducing spermatogenesis in subjects with hypogonadotropic hypogonadism (HHG) and azoospermia. An extensive Medline and Embase search was performed including the following words: 'gonadotropins' or 'GnRH', 'infertility', 'hypogonadotropic', 'hypogonadism' and limited to studies in male humans. Overall, 44 and 16 studies were retrieved for gonadotropin and GnRH therapy, respectively. Of those, 43 and 16 considered the appearance of at least one spermatozoa in semen, whereas 26 and 10 considered sperm concentration upon gonadotropin and GnRH, respectively. The combination of the study results showed an overall success rate of 75% (69-81) and 75% (60-85) in achieving spermatogenesis, with a mean sperm concentration obtained of 5.92 (4.72-7.13) and 4.27 (1.80-6.74) million/mL for gonadotropin and GnRH therapy, respectively. The results upon gonadotropin were significantly worse in studies involving only subjects with a pre-pubertal onset HHG, as compared with studies involving a mixed population of pre- and post-pubertal onset [68% (58-77) vs. 84% (76-89), p = 0.011 and 3.37 (2.25-4.49) vs. 12.94 (8.00-17.88) million/mL, p < 0.0001; for dichotomous and continuous data, respectively]. A similar effect was observed also upon GnRH. No difference in terms of successful achievement of spermatogenesis and sperm concentration was found for different FSH preparations. Previous use of testosterone replacement therapy (TRT) did not affect the results obtained with gonadotropins. Finally, a higher success rate was found for subjects with lower levels of gonadotropins at the baseline and for those using both human chorionic gonadotropin and FSH. Gonadotropin therapy, even with urinary derivatives, is a suitable option in inducing/restoring fertility in azoospermic HHG subjects. Gonadotropins appear to be more efficacious in subjects with a pure secondary nature (low gonadotropins) and a post-pubertal onset of the disorder, whereas previous TRT does not affect outcome.

Select patients with hypogonadotropic hypogonadism may respond to treatment with clomiphene citrate

OBJECTIVE

To review the management of male hypogonadotropic hypogonadism (HH) and evaluate the efficacy of clomiphene citrate (CC).

DESIGN

Retrospective review.

SETTING

Two university-based urology clinics.

PATIENT(S)

Ten patients referred for male infertility evaluation.

INTERVENTION(S)

Patients were treated with either clomiphene citrate or injectable gonadotropins.

MAIN OUTCOME MEASURE(S)

Changes in seminal parameters, gonadotropin levels, serum testosterone, and pregnancy.

RESULT(S)

Ten men who were evaluated for infertility were diagnosed with HH. Four had Kallmann's syndrome, four idiopathic HH, and two panhypopituitarism. Eight patients were azoospermic, and two were oligospermic on presentation. Three of the four men with adult-onset idiopathic HH responded to CC alone with increases in testosterone, FSH, and LH. Semen parameters in this group also improved, and two of the three men achieved pregnancies with CC alone. Out of the ten men actively attempting conception, four pregnancies were achieved. Three pregnancies (two with CC and one with gonadotropins) were in men diagnosed with adult-onset idiopathic forms of HH.

CONCLUSION(S)

Select patients with adult-onset idiopathic forms of HH may benefit from a trial of clomiphene citrate.

Endocrine causes of male infertility

Although endocrinopathies are not often seen in infertile men, these disorders are clinically significant; they often have potentially serious medical significance, regardless of fertility issues. Correction of these disorders represents a possible way to restore normal fertility for the male partner. Male fertility is critically dependent upon a normal hormonal milieu. The hypothalamic-pituitary-gonadal axis is quite sensitive to disruption by endocrine disorders and other generalized medical disorders. Thus, male infertility is occasionally the presenting sign for significant underlying medical disease; it is important to properly evaluate these patients.

Predicting pregnancy and spermatogenesis by survival analysis during gonadotrophin treatment of gonadotrophin-deficient infertile men

BACKGROUND

Predictors of fertility or spermatogenesis during gonadotrophin therapy of gonadotrophin-deficient men remain poorly defined.

METHODS AND RESULTS

In order to evaluate potential predictors, this study evaluated 29 consecutive gonadotrophin-deficient men all desiring paternity who received 43 courses of therapy in one centre between 1982 and 1998. The Kaplan-Meier survival analysis estimates of median (SE) time to a sperm concentration of >0, >5 and >20 x 10(6)/ml were 5.5 (1.1), 12.4 (2.3) and 29.1 (1.9) months respectively. Conception occurred in 22/43 cycles (with eight men achieving two pregnancies) with a median (SE) Kaplan-Meier estimate of 20.5 (4.7) months. The median sperm concentration at conception was 5.0 (SE 2.0; range 0.0-59.5) x 10(6)/ml. Multivariate correlated Cox proportional hazards models predicting these same sperm thresholds and conception were developed by forward stepwise variable selection with verification of the model by backward stepping. Larger testicular volume, prior gonadotrophin therapy, completion of puberty, older age, the absence of adverse fertility factors and the absence of multiple pituitary hormone deficiency predicted a favourable response. Multivariate modelling suggests that the two most important predictors of sperm output are testicular volume and pubertal status. The most important potentially modifiable predictor was prior gonadotrophin therapy. The efficacy of recombinant and urinary FSH were similar. Prior androgen therapy and partner's age did not appear to be significant.

CONCLUSIONS

Since prolonged treatment may be required to induce spermatogenesis, attention to these predictors may allow appropriate early use of advanced reproductive technologies.

Induction of testicular growth and spermatogenesis by pulsatile, intravenous administration of gonadotrophin-releasing hormone in patients with hypogonadotrophic hypogonadism

OBJECTIVE

To induce testicular growth including spermatogenesis, 38 patients with hypogonadotrophic hypogonadism were treated with long-term pulsatile GnRH administration.

PATIENTS

The group of patients comprised 17 individuals with idiopathic hypogonadotrophic hypogonadism, 11 with Kallmann's syndrome, four with multiple pituitary hormone deficiencies and six with a secondary hypogonadotrophic hypogonadism due to surgical removal of a brain tumour. Thirteen patients (seven with idiopathic hypogonadotrophic hypogonadism and six with Kallmann's syndrome) had undescended testes, of whom six had undergone surgery on both testes and four on one testis. Sixteen of the 17 had previously received androgen therapy and six others had received gonadotrophin treatment, of whom three had long-term treatment to induce testicular development, without success.

TREATMENT

GnRH was administered intravenously in a dose of 2-20 micrograms per pulse every 90 minutes. After GnRH discontinuation, hCG treatment was instituted, 1500-3000 IU (i.m.) twice weekly.

RESULTS

During treatment plasma levels of LH, FSH and testosterone increased. In 35 out of the 38 patients plasma testosterone levels increased into the normal adult range. In all patients testicular volume increased. Mean pretreatment testicular volume per patient group ranged from 2.4 to 4.8 ml and increased to 11.5-18.1 ml by the end of treatment. There was a significant difference in the achieved testicular volumes between the patients with Kallmann's syndrome and the brain tumour patients. GnRH treatment mean lasted between 46 and 75 weeks in the different groups. On hCG therapy, testicular development was either maintained or improved. Semen analysis revealed the presence of spermatogenesis in 31 out of the 38 patients (26 patients already on GnRH, and in another five patients on hCG therapy). All three patients pretreated with gonadotrophins as well as three patients with bilateral testicular surgery developed a detectable sperm count. In 19 adolescent patients with growth potential, an adequate height velocity was observed during GnRH treatment.

CONCLUSIONS

GnRH is a feasible way to induce testicular growth as well as spermatogenesis in hypogonadotrophic male patients, even in patients in whom gonadotrophin treatment has failed. After GnRH treatment, hCG alone can maintain or even improve testicular development, including spermatogenesis. GnRH treatment may also induce a physiological growth spurt in hypogonadotrophic adolescents.

Circadian rhythm of plasma testosterone in men with idiopathic hypogonadotrophic hypogonadism before and during pulsatile administration of gonadotrophin-releasing hormone

OBJECTIVE

The aim was to investigate whether a pulsatile discharge of LH from the pituitary is necessary to achieve the circadian secretion of testosterone.

DESIGN

The daily rhythm of the androgen has been studied in patients with idiopathic hypogonadotrophic hypogonadism (IHH) both in the absence of therapy and during pulsatile administration of gonadotrophin releasing hormone (GnRH).

PATIENTS

Six patients with IHH and ten normal subjects were analysed. Blood sampling was performed at 2-hourly intervals, for 24 hours. The IHH patients then received synthetic GnRH i.v. at the rate of one pulse every 2 hours (10 micrograms/pulse). On day 11 of treatment, blood samples were taken for the rhythm analysis every 2 hours, for 24 hours.

MEASUREMENTS

Plasma testosterone and LH were measured in the individual samples by radioimmunoassay. Evaluation of the rhythm was performed by cosinor analysis.

RESULTS

A significant circadian rhythm of plasma testosterone was statistically validated in the normal subjects, whereas no rhythm was detected in the IHH patients in the absence of therapy. On day 11 of GnRH pulsatile administration the IHH patients showed normal testosterone levels and a statistically significant circadian rhythm of the androgen was evident, with acrophase between 0700 and 0800 h. Moreover, the amplitude, acrophase and mesor of testosterone rhythm in IHH patients in the course of treatment were statistically indistinguishable from the corresponding values in the normal subjects. Plasma LH did not show statistically significant circadian variations, either in the control group or in the IHH patients before or during therapy.

CONCLUSIONS

We conclude that a physiological circadian rhythm of plasma testosterone can be obtained, in IHH men, by treatment with GnRH. Since the pulsatile administration of exogenous GnRH at constant doses induced a circadian rhythm in testosterone and no daily variations in LH were evident, we suggest that, although a pulsatile secretion of LH is probably necessary for the synchronization of the circadian rhythm with acrophase in the morning, the testosterone variations might be the results of a local testicular modulation of LH action.

Initiation of spermatogenesis and successful in vitro fertilization in an infertile male with panhypopituitarism; superiority of pulsatile LH-RH over gonadotropins? A case report

This case report describes an infertile male patient with panhypopituitarism, presumably caused by traumatic breech delivery. Previous hMG/hCG treatment had failed to induce spermatogenesis. Initiation of the production of motile and morphological normal sperm, despite persisting significant oligozoospermia was established with s.c. pulsatile LH-RH treatment. Spermatogenesis could be maintained with i.m. hCG injections bi-weekly. Later, fruitful in vitro fertilization (IVF) resulted in the birth of a healthy daughter.

Pulsatile LHRH therapy in patients with oligozoospermia and disturbed LH pulsatility

Pulsatile administration of LHRH can drive the pituitary to secrete LH and FSH in a pattern that closely mimics the physiological pattern of the hypothalamic-pituitary-gonadal axis. As there is evidence that infertility in some men is due to dysfunction of this axis, 14 men with reported infertility of more than 2 years duration were treated by long-term pulsatile LHRH therapy. They were 24-42 years of age, with variable degrees of oligozoospermia, elevated FSH levels but normal LH and testosterone levels. The number of endogenous LH pulses/24 h was less than eight in all 14 subjects. The degree of testicular damage was assessed semi-thin sections prepared from biopsies of both testes. Scores for spermatogonia per seminiferous tubule (SPT) were calculated from the actual number of Ad-spermatogonia/tubule. Patients were grouped according to sperm density and SPT score (groups I-III). Pulsatile LHRH therapy was administered by means of a portable infusion pump; 4 micrograms LHRH were administered subcutaneously every 120 min for a period of 6 months. This treatment restored the normal pattern of LH secretion to 12 LH pulses/24 h in all patients. A statistically significant decrease of mean FSH levels to normal, and an increase of mean LH levels was observed in most of the 14 patients. Testosterone values did not change in any group. Marked improvement of the sperm count was observed in eight out of 14 patients (groups I and II) and three pregnancies were reported during the treatment periods. These results suggest that some states of male infertility are due to hormonal dysregulation and that these patients may benefit from pulsatile LHRH therapy.