I. Basic concept
A couple of childbearing age who have lived together for more than one year without any contraceptive measures and whose wife is not pregnant, and the cause of which occurs in the male partner, is called male infertility.
Strictly speaking, male infertility is not an independent disease, but a result of a combination of factors.
The causes of male infertility are complex, and endocrine dysfunction or gonadal axis dysfunction is only one of them.
Second, the diagnosis process of male infertility
1, the WHO recommended clinical diagnosis process of male infertility
WHO’s diagnostic process of male infertility
3. The physiology of male reproductive endocrine regulation
(i) The main hormones and their roles in regulating male reproductive endocrine
1.Gonadotropin-releasing hormone (GnRH) secreted by the hypothalamus, whose target is the pituitary gland. It causes the pituitary gland to secrete corresponding hormones.
2.The hormones secreted by the pituitary gland mainly include follicle stimulating hormone (FSH), luteinizing hormone (LH) and prolactin (PRL), the target of FSH is the testicular varicocele, which is a hormone that promotes sperm production, it can stimulate the spermatogenesis of the epithelium of the testicular varicocele in men, thus producing sperm. It is able to stimulate the synthesis and secretion of androgens by the interstitial cells. PRL plays an important role in maintaining normal endocrine function in men.
The testes secrete androgens (T) and a small amount of estrogen; T is important for maintaining male secondary sexual characteristics, maintaining normal sexual function and promoting the maturation of sperm.
(ii) Normal physiological regulation of the male reproductive axis
Sperm production
LH = luteinizing hormone FSH = follicle stimulating hormone T = testosterone DHT = dihydrotestosterone
E2 = estradiol LH-RH = luteinizing hormone releasing hormone [+] positive feedback [-] negative feedback
The determination of the clinical significance of sex hormones must be combined with clinical symptoms and various other tests for a comprehensive analysis.
T, E2, FSH, LH are normal basically can discharge reproductive endocrine diseases, but cannot completely exclude varicocele and accessory gonadal lesions. In case of azoospermia infertility, the vas deferens should be further examined for obstruction.
Low T, FSH and LH are generally considered to be hypothalamic and pituitary hypofunction, secondary to reduced testicular function. Such as Kallmann syndrome or acquired organic hypothalamic pituitary lesion or injury.
Elevated PRL, low FSH, LH or normal low limit for hyperprolactinemia, suggesting pituitary tumor or pituitary microadenoma.
IV. Common causes of endocrine male infertility
In general, they can be summarized into two main categories, namely.
(i) primary testicular dysfunction
It is the testicular spermatogenic dysfunction caused by genetic or acquired defects. The following lesions are common.
Congenital azoospermia is congenital absence of the testes. The clinical manifestation is infertility due to the absence of secondary sexual characteristics appearing at puberty and the absence of sperm in the semen. In these patients, the chromosome is usually 46XY. Unilateral azoospermia is usually found on the right side, and is often accompanied by contralateral cryptorchidism.
Sex hormone examination shows that FSH and LH are elevated and T is very low.
Clinical manifestations of Kallmann syndrome: small testes with loss or hyposmia, a congenital recessive disorder. Semen analysis is devoid of sperm.
Sex hormone examination: FSH and LH are very low, and T is also low.
Congenital testicular hypoplasia syndrome (Klinefelter syndrome) is also known as testicular varicocele dysplasia. The clinical manifestations are small testes, small penis, and mostly associated with breast development. The typical cell karyotype is 47XXY. semen analysis is devoid of spermatozoa.
Sex hormone examination: FSH level is very high and T is very low.
Only support cell syndrome clinical manifestations male secondary sex characteristics are normally developed, but testes are slightly small. Semen analysis azoospermia.
Sex hormone examination: FSH is elevated, LH is normal, and chromosomes can be normal.
Others are Prader-Will syndrome (sexually naïve hypotonia syndrome), Frohich syndrome (obese reproductive incompetence syndrome), and simple LH deficiency (fertile eunuch syndrome).
(ii) Secondary testicular dysfunction
Normal human reproductive activity depends on the natural physiological regulation of male hypothalamic-pituitary-gonadal axis function. Whatever the cause of this gonadal axis dysfunction, it can cause male infertility. The common causes are.
⒈ testicular mesenchymal cell tumor because of the secretion of more androgens, metabolized by the liver into estrogen, resulting in an imbalance in the ratio of estrogen to androgen in the body. Clinical manifestations are male feminization, breast enlargement, erectile dysfunction, etc. Semen analysis appears as oligozoospermia.
Sex hormone examination: estrogen is significantly elevated. Other hormone levels are basically normal.
Peal hyperprolactinemia clinical manifestations of severe cases may have breast development, erectile dysfunction, etc. Semen analysis may show oligozoospermia. Sex hormone examination: PRL is elevated, other hormone levels are normal. Generally, MRI of pituitary gland should be done.
Semen analysis may show oligospermia and in severe cases, azoospermia.
Sex hormone test: FSH is significantly elevated.
Singular thyroid disease is commonly seen as hyper- or hypothyroidism. Semen analysis may reveal oligospermia. The hormones T3, T4, and TSH can be used to confirm the diagnosis.
Be careful with adrenal gland disorders
(1) Congenital adrenal hyperplasia may present with testicular dysplasia due to excessive secretion of testosterone and thus suppression of gonadotropin secretion by the pituitary gland. Semen analysis is devoid of sperm.
Hormonal examination: elevated T and decreased FSH and LH.
(2) Feminization Adrenocortical tumors cause feminization in men due to excessive secretion of estrogen, which is manifested by breast development testicular tissue atrophy. Sperm analysis is seen as oligospermia or azoospermia.
(3) Addison’s disease is caused by cortisol or aldosterone deficiency due to atrophy or destruction of the adrenal cortex. If adrenocortical hormone deficiency due to pituitary or hypothalamic disease is present, testosterone secretion is reduced and semen analysis reveals oligospermia or azoospermia.
(4) Cushing’s syndrome is due to excessive secretion of adrenocorticotropic hormone, which inhibits the secretion of gonadotropin by the pituitary gland. Clinical manifestations include decreased libido and erectile dysfunction. Semen analysis reveals oligospermia.
6, diabetes many studies have shown that glucose plays an important role in the normal spermatogenesis process. Blood glucose is the main energy source for the spermatogenic epithelium, while the non-spermatogenic epithelium (supporting cells and interstitial cells) in the testis mainly relies on lipid metabolism for energy supply. Hypospermatogenesis is often seen due to impaired glucose utilization. Weak spermatozoa or oligospermia can be seen in semen analysis.
V. Treatment of endocrine male infertility
(i) Modern medical treatment
The basic principle: to clarify the cause and target treatment. Treatment should be abandoned for azoospermia male infertility caused by congenital or genetic reasons.
(ii) Chinese medicine treatment
Ancestral medicine believes that the kidneys store sperm, the main reproduction, the abundance of kidney sperm, the presence or absence of heavenly sperm, the adequacy of qi and blood, and the coordination of visceral functions directly affect the fertility of men. Among the internal organs, the most closely related to infertility are the heart, liver, spleen and kidney, of which the kidney is the most important.