Spermatogenesis Stimulation

Testosterone And Prenatal Development

The induction of spermatogenesis in patients with hypogonadotropic hypogonadism requires testicular stimulation with GnRH or gonadotropins. Various preparations are available see Table 1 to reach this goal, each with advantages and disadvantages. Because the maturation of spermatogonia to mature sperm takes approx 70 d, the first sperm usually do not appear in the ejaculate for at least 3 mo, but it may take 2 yr for patients with congenital hypogonadotropic hypogonadism to become sperm...

Physiopathology of Hypogonadism

Acromegaly is a disease characterized by the excessive production of growth hormone GH . More than 99 of cases of acromegaly result from a tumor of the pituitary gland secreting either GH or both GH and PRL. Gangliocytomas of the hypothalamus or pituitary and ectopic neuroendocrine tumors secreting GH-releasing hormone GHRH account for less than 1 33 . Hypogonadism has been reported in 49 to 70 of patients with acromegaly 31,34 . Secretion of PRL by the tumor, together with GH or stalk...

Management Of Delayed Puberty

For induction of puberty in boys with constitutional delay of puberty, the indication for treatment is usually psychosocial boys with delayed puberty may suffer because of short stature and lack of pubertal progression. This distress may affect their school performance and their social relationships. Testosterone esters, given intramuscularly, remain the most commonly used treatment approach therapy can be started with 50 mg of a mixture of testosterone propionate and testosterone enanthate...

Hormone Production Sexual Development and Activity Hormone Production

Cryptorchid Testicular Volume

Testosterone levels are generally normal in men with cryptorchidism, even those who were not treated 73,130 . Although testosterone levels are within the normal range in men who were formerly cryptorchid see Fig. 3 without other problems, a Fig. 4. Testosterone levels ng dL in men who were formerly cryptorchid plotted against age of orchidopexy. These data suggest lower levels in men with orchiopexy at older ages 1 . Fig. 4. Testosterone levels ng dL in men who were formerly cryptorchid plotted...

Pathophysiology Of Hivinfection In The Reproductive Tract And Potential Mechanisms Of Gonadal Dysfunction

Testicular atrophy is a common finding in autopsy series of patients infected with HIV 8-11 . Histological examination of the testes reveals a spectrum of abnormalities, including hypospermatogenesis, spermatogenic arrest, and Sertoli cell-only pheno-types 11 . In addition to the loss of germ cells and atrophy, the seminiferous tubules exhibit basement membrane thickening and peritubular fibrosis 8,9 . Common abnormalities in semen include leukocytospermia, lower ejaculation volume and total...

Clinical Features Of Klinefelters Syndrome

Klinefelter Syndrome

The clinical manifestations of KS are those of prepubertal androgen deficiency and infertility. Because testicular failure occurs before puberty, the developmental changes Fig. 2. An individual with Klinefelter's syndrome. Note tall body proportions, gynecomastia, relative paucity of facial and body hair, and small testis. Photos courtesy of Dr. C. Alvin Paulsen. Fig. 2. An individual with Klinefelter's syndrome. Note tall body proportions, gynecomastia, relative paucity of facial and body...

Pathophysiology Of Klinefelters Syndrome

Testicular Biopsy Klinefelter

Most cases of KS occur through sporadic chromosomal nondisjunction during parental gametogenesis in either the sperm or the egg. A seminal study using DNA probes to X chromosome restriction-site polymorphisms demonstrated that in one series of 32 individuals with KS the additional X chromosome was of paternal origin in 17 53 of cases and of maternal origin in 14 44 of cases and resulted from a postzygotic mitotic error in 1 3 case see Table 1 10 . Because these are sporadic errors in...

Occupational Lifestyle Effects on Scrotal Temperature

Scrotal Hyperthermia

Another situation in which occupational effects on male reproductive function might become apparent is if the occupational effect applies to a large proportion of men. It is possible that scrotal heating may be one such example. Scrotal, and therefore testicular, temperature has to be maintained some 3-4 C lower than core body temperature if normal spermatogenesis is to occur see Fig. 2 , and interference with the normal scrotal cooling process can profoundly affect sperm production, quality,...

Exercise Hypogonadal Males Basal Hormonal Responses

Testosterone Levels

Retrospective comparative studies examining isolated, single blood samples have found lower testosterone levels in chronically endurance-trained males. The subjects in those studies were typically distance runners who had been involved with the physical-training aspects of their sport for 1 to 15 yr. In those studies, total and free-testosterone levels in the endurance-trained men were only 60-85 of the levels of matched sedentary controls 7,35,54,56-58 . Many of the early studies reporting...

Congenital Idiopathic Hypogonadotropic Hypogonadism CIHH Definition

Delayed Adolescence

CIHH is characterized by an isolated defect in GnRH secretion or function. Criteria for the diagnosis of CIHH include 1 decreased T levels in the hypogonadal range e.g., lt 3.5 nmol L , 2 low normal gonadotropin levels representing absent or reduced GnRH secretion, 3 otherwise normal hormonal testing of the anterior pituitary, 4 a normal ferritin level, and, 5 normal radiographic imaging of the hypothalamic-pitu-itary region. Familial CIHH was reported in 1944, in association with anosmia and...

Secondary Hypogonadotropism

In male patients with 21-hydroxylase deficiency, as in affected females, adrenal androgens may suppress the hypothalamic-pituitary-gonadal axis, both directly and after conversion to estrogens, thereby leading to hypogonadotropic hypogonadism 12-14 . Augarten et al. described a patient who was referred for secondary infertility and was diagnosed with nonclassic 21-hydroxylase deficiency, as was his daughter 58 . Serum FSH and LH levels were decreased and unresponsive to GnRH stimulation....

Leydig Cell Development

Reinke Crystals Leydig

Leydig cells were first described by the German histologist Franz Leydig in 1850 1 . In all mammalian species, Leydig cells are located in the interstitial compartment of the testis, between and surrounding the seminiferous tubules 2 . Human Leydig cells are epithelioid and ovoid or polygonal. Other cytological features include eosinophilic cytoplasm, euchromatic round eccentric nuclei with a peripheral distribution of heterochro-matin, and conspicuous nucleolus. The predominant cytoplasmic...

Normal Sex Steps Amages

Hypogonadism Klinefelter Syndrome

Cardiovascular disease is more common in men than in menstruating women, and more common in women with elevated serum androgen levels, as in polycystic ovary syndrome PCOS 1 or type 2 diabetes 2 than in normal women. Interest in the relationship between androgens and cardiovascular disease has been stimulated further by the emerging use of testosterone replacement for older men because of concern that cardiovascular risk might increase as a side effect of therapy. The relationship between...

Aging of Leydig Cells

Reproductive function declines as men grow older. An age-associated decline in plasma testosterone concentration occurs even in healthy men (104,105), although there is considerable variation in the age of onset (106). The level of testosterone in the blood stream declines on average by 1.2 each year for men over 40 yr of age. Because SHBG rises, the level of free (bioavailable) testosterone in the blood decreases more with age compared to total testosterone (106,107). Because clearance of...