Male Infertility

Infertility is defined as the inability to achieve a spontaneous pregnancy in sexually active couples who have been having unprotected sexual intercourse for at least one year. When it only affects the male, it is referred to as male infertility.

Depending on the degree of this inability, male infertility can be classified into several types:

• Primary infertility: the inability to achieve a first pregnancy.
• Secondary infertility: the inability to achieve a new pregnancy when there has been at least one previous conception.
• Absolute infertility or male sterility: it is irreversible, making it impossible to have offspring.
• Relative infertility or subfertility: more time than usual is needed to achieve a pregnancy. The causes of this can be reversible, and various treatments can facilitate conception.

Depending on the cause, types of male infertility include:

• Male infertility due to pre-testicular or endocrine factors: hormonal alterations affect the development of the testicles and, consequently, sperm production.
• Male infertility due to testicular factors: a congenital or acquired condition in the testicles that prevents proper sperm formation.
• Male infertility due to post-testicular factors: abnormalities in the seminal ducts prevent sperm from being ejaculated.
• Male infertility due to sperm factors: the most common case. Sperm show abnormalities in morphology, motility, vitality, or concentration:
• Azoospermia: absence of sperm in the ejaculate, either because they are not produced (secretory azoospermia) or because they cannot be expelled (obstructive azoospermia).
• Oligozoospermia: low sperm concentration (less than 15 million per milliliter of ejaculate).
• Cryptozoospermia: very low concentration (less than 100,000 per milliliter).
• Asthenozoospermia: poor motility.
• Teratozoospermia: presence of many sperm with abnormal morphology.
• Necrospermia: high number of dead sperm.

Symptoms

The only noticeable sign of infertility is the inability to fertilize. However, the underlying causes of this inability may show symptoms that signal possible male infertility:

• Low libido, i.e., decreased sexual desire.
• Erectile problems: difficulty achieving or maintaining an erection.
• Ejaculation problems: difficulty ejaculating or low volume of ejaculate.
• Altered semen: too watery, too thick, abnormal color, or strong odor.
• Urinary changes or pain when urinating.
• Varicose veins or lumps in the testicles.
• Pain or swelling in the testicles.
• Testicles smaller than normal.
• Hormonal changes: voice changes, body hair loss, abnormal breast growth, or decreased muscle mass.

Causes

As previously mentioned, there are four factors that cause male infertility. Each of them has specific causes.

Hormonal alterations that affect both sperm production and formation are usually due to congenital issues:

• Hypogonadism (low testosterone levels).
• Hyperthyroidism.
• Hypothyroidism.
• Diabetes.
• High levels of prolactin, which reduce testosterone production.

Testicular pathologies that affect sperm production are mainly caused by:

• Genetic mutations or inherited conditions, such as cystic fibrosis or defects in Y chromosome genes.
• Testicular conditions:
• Undescended or abnormally small testicles.
• Varicocele: swelling of the veins that drain the testicle.
• Infections that cause testicular inflammation.
• Hydrocele: excessive fluid accumulation in the spermatic cord.

Ejaculation problems may be caused by:

• Obstructions in the seminal ducts resulting from trauma or infections.
• Congenital absence of the vas deferens.
• Erectile dysfunction that prevents ejaculation.
• Retrograde ejaculation: semen is directed into the bladder.

Abnormal sperm quality may be caused by:

• Physical alterations as described earlier.
• Anti-sperm antibodies: sometimes, when sperm come into contact with blood due to prostatitis or surgery, the immune system releases antibodies that identify sperm as invaders and attempt to eliminate them.

Furthermore, male fertility can be seriously affected by external factors that impact sperm production and function:

• Use of anabolic steroids and opiates.
• Chemotherapy and other medications.
• Prolonged exposure to radiation, industrial chemicals, or heavy metals.

Risk Factors

There are various conditions that increase the likelihood of male infertility:

• Harmful habits: smoking, excessive alcohol use, and drug consumption.
• Exposure to toxic substances.
• Overweight or obesity.
• History of infections or sexually transmitted diseases.
• History of injuries or trauma to the testicles.
• Family history.
• Exposure of the genitals to very high temperatures.
• Abdominal or pelvic surgeries.
• Presence of congenital conditions or malformations affecting sperm production.
• Chemotherapy treatment.

Complications

The main complication of male infertility is the possibility that it may be irreversible, meaning the cause may have no solution. Additionally, infertility, even with treatment, can lead to high levels of stress and frustration for both the individual and the couple. Furthermore, recent studies link a low or absent sperm count with the risk of developing certain types of cancer, such as testicular, colon, or prostate cancer.

Prevention

Infertility caused by congenital factors cannot be prevented. However, it is possible to act on external risk factors affecting fertility and take certain measures:

• Avoid smoking, alcohol, and drug use.
• Avoid prolonged exposure to toxic substances.
• Maintain a healthy weight.
• Avoid prolonged exposure to heat in the testicles.
• Use condoms to prevent sexually transmitted infections.

Which doctor treats male infertility?

Male infertility is evaluated and treated by specialists in urology and assisted reproduction units.