Etiology and Pathology of Male Infertility (Part 2): Genetics, Immunity, and Reproductive Tract Infections

**(III) Hereditary Diseases and Male Infertility**

1. Sex chromosome abnormalities

Cytogenetic studies have confirmed that infertility caused by cytogenetic abnormalities accounts for 2% to 50% of cases.

Chromosomal abnormalities are a significant contributing factor to 21% of cases. Abnormalities in chromosomes or genes can affect sexual function.

The glands, leading to impaired spermatogenesis in the testes, can cause testicular dysfunction and infertility. In severe cases of oligospermia and...

The incidence of cytogenetic disorders is particularly high among patients with azoospermia compared to the general population.

2. Autosomal aberrations

Autosomal translocations are more common in male infertility patients than in men with normal fertility, and occur more frequently.

The most common translocation is D/D chromosome translocation, followed by Y/Y chromosome translocation. The patient's secondary sexual characteristics and testicular size are also relevant.

Generally, there are no abnormalities. The most common histological feature of the testes is a nonspecific decrease in sperm count, with sperm appearing after spermatogenesis.

Damage occurs during the process. Another type of autosomal aberration is a chromosome with extra small markers, these small-marked chromosomes...

It affects both somatic cells and germ cells. The patient has severe testicular atrophy and no spermatogenesis. Autosomal abnormalities.

Few patients with this condition are able to have children.

3. Chromosomal abnormalities during meiosis

In male infertility patients, those infertile due to azoospermia all had testicular biopsies confirming spermatogenesis.

Significant chromosomal abnormalities were observed during meiosis in primary spermatocytes, with the first meiotic division of primary spermatocytes resulting from the mutual exchange of homologous chromosomes.

The rate of mutation decreases, and asymmetric bivalents, multivalents, monovalents, and chromosome fragments are present during the terminal phase. The above-mentioned diseases...

Physiological changes cause sperm development to arrest at the spermatocyte level, thus preventing further differentiation into sperm, resulting in...

Infertility.

4. Turner syndrome in men

The majority of patients with this disease have a 46,XY karyotype.

A small number of cases involve chimerism. Infertility is caused by impaired spermatogenesis and reduced androgen production.

5. Del Caslilllo syndrome

Patients with this syndrome have only Sertoli cells in their seminiferous tubules but no sperm production, resulting in azoospermia and infertility.

(Education).

6. Hereditary enzyme deficiency

Certain inherited enzyme deficiencies can lead to male infertility. Patients experience gonadal atrophy and suppressed spermatogenesis.

The mode of inheritance is autosomal recessive (AR), and this type of genetic deficiency of steroid hormone synthase...

Symptoms can directly affect androgen synthesis, leading to infertility.

**(iv) Immune dysfunction and male infertility**

Autoimmunity and alloimmunity triggered by immunogenic substances in the reproductive system can cause infertility in humans.

Sperm autoimmune reactions are a significant cause of male infertility. Furthermore, reproductive activities...

Many key processes involve specific antigenic substances, under certain internal or external conditions.

These specific antibodies primarily activate the body's own immune system, thereby interfering with normal reproductive physiology.

The process can affect fertility.

**(V) Reproductive System Infections and Male Infertility**

Both specific and non-specific infections of the reproductive system can affect spermatogenesis, motility, and transport, and inhibit sperm production.

Inhibition of accessory gland secretion can lead to infectious infertility. Currently, the incidence of sexually transmitted diseases is on the rise worldwide.

Sexually transmitted diseases (STDs) can cause inflammatory damage and fibrotic changes in the reproductive system, leading to infectious male infertility.

The main reason is... Additionally, inflammation of the reproductive system caused by mumps and tuberculosis can lead to male infertility.

It is also quite common.

1. The impact of male reproductive tract infections on sperm motility

Male reproductive tract infections include bacterial infections, mycoplasma infections, and infections caused by other pathogens.

Both can cause inflammation of the reproductive system and affect sperm motility.

2. The impact of male reproductive tract infections on sperm count and morphology

Male reproductive tract infections include acute and chronic infections.

(1) The effect of acute infection on sperm count: Acute orchitis can cause extensive damage to the testicular parenchyma.

It can lead to decreased or absent testicular spermatogenesis. Acute epididymitis can obstruct the vas deferens and affect adjacent testicular spermatogenesis.

The epididymis atrophies, and this obstruction is reversible. However, during acute epididymitis, bacterial invasion occurs.

Damage to adjacent testicular parenchyma is irreversible, and severe damage can manifest as oligospermia or azoospermia.

Acute prostatitis and/or seminal vesiculitis can cause edema and compression of the ejaculatory ducts, leading to complete or incomplete obstruction.

Most cases can be restored to normal after antibiotic treatment.

(2) Effects of chronic infection on sperm count and morphology: Chronic prostatitis rarely causes ejaculatory duct obstruction.

While it may obstruct the flow of sperm, whether it causes abnormal changes in sperm count and morphology is not yet fully understood. Chronic epididymitis and vas deferens...

Infections of the vas deferens can cause obstruction of the vas deferens. Chronic orchitis can lead to testicular atrophy and stiffening, resulting in loss of spermatogenesis.

Function.

3. Effects of several specific infections on sperm

(1) Gonococcal infection: Gonococcal urethritis is often complicated by prostatitis and epididymitis, which can affect sperm motility.

Urethral stricture can result from the treatment of periurethral gland infection caused by gonococcal infection.

Another complication of gonococcal infection is obstruction of the vas deferens.

(2) Reproductive tract tuberculosis: Reproductive tract tuberculosis mainly causes incomplete or complete obstruction of the vas deferens.

Epididymal tuberculosis can cause obstruction of the epididymal duct and proximal vas deferens. Prostatic and/or seminal vesicle tuberculosis can cause ejaculation.

Vascular obstruction.

(3) Mumps complicated with orchitis: Before puberty, mumps complicated with orchitis will not lead to adverse outcomes.

The incidence of this type of orchitis is approximately 20% in mumps patients around puberty. Unilateral testicular involvement...

Damage to one testicle reduces sperm density but does not affect fertility; however, damage to both testicles can lead to severe oligospermia.

Or azoospermia.

4. Other changes in semen caused by male reproductive tract infections

In male reproductive tract infections, 60%–80% of cases involve dysfunction of accessory gland secretion, particularly the prostate gland.

Characteristic products such as zinc, calcium, magnesium, citric acid, and acid phosphatase can all be reduced. This is especially true if the seminal vesicles are infected in the reproductive tract.

Severe damage may reduce the fructose content in seminal plasma. The sperm-stimulating factor secreted by the seminal vesicles has...

The effect of liquefaction factors secreted by the prostate gland is counteracted, leading to semen non-liquefaction and high viscosity during reproductive tract infections.

The birth rate increased significantly (38.5%).