Overview
Male infertility is defined as the failure to achieve conception after one year of regular unprotected intercourse. Male factors contribute to approximately fifty percent of infertility cases and often coexist with female causes. The condition arises from disorders of the male reproductive system affecting sperm production, sperm quality, or sperm delivery.
Causes may include lifestyle factors, genetic abnormalities, hormonal imbalance, infections, or systemic illness. A structured workup identifies underlying causes and guides treatment, while laboratory findings help assess prognosis and future reproductive potential.
Symptoms
The primary presentation is the inability to conceive despite regular unprotected intercourse. Abnormal semen parameters such as low volume, reduced sperm concentration, poor motility, low vitality, or abnormal morphology indicate impaired fertility potential.
Azoospermia, the absence of sperm in semen, requires further classification into obstructive or non-obstructive types. Hormonal disturbances such as low testosterone, elevated prolactin, or thyroid dysfunction may also affect sperm production. Infections of the genital tract may present with abnormal semen findings. Structural abnormalities such as a varicocele may be detected on ultrasound.
Causes
Male infertility results from multiple mechanisms. Semen abnormalities include low sperm concentration, reduced motility, abnormal morphology, or decreased vitality. Hormonal causes involve disturbances in FSH, LH, testosterone, prolactin, and thyroid hormones.
Hypogonadotropic hypogonadism may show low FSH, LH, and testosterone, while primary testicular failure presents with elevated FSH and LH with low testosterone. Isolated testosterone deficiency and thyroid dysfunction also impair fertility.
Genetic causes include chromosomal abnormalities detected by karyotype analysis, Y chromosome microdeletions affecting spermatogenesis, and CFTR gene mutations associated with congenital absence of the vas deferens. Infections such as Chlamydia trachomatis or Ureaplasma may impair sperm function. Immunological factors include antisperm antibodies.
Structural causes include varicocele or obstructive lesions affecting sperm transport. Reactive oxygen species and sperm DNA fragmentation may reduce fertilization capacity.
Risk Factors
Lifestyle and systemic illnesses contribute to impaired sperm quality. Genetic abnormalities increase the risk in men with recurrent infertility or azoospermia. Hormonal imbalance affects sperm production and endocrine function. Genital tract infections predispose to inflammatory damage. Structural abnormalities such as a varicocele disrupt the normal testicular environment.
Elevated oxidative stress and DNA fragmentation negatively affect sperm function. Azoospermia requires careful evaluation to distinguish obstructive from non-obstructive causes. Repeated abnormal semen analyses strengthen the diagnosis and guide further hormonal, genetic, and imaging investigations.
Prevention
Early evaluation through semen analysis remains the first-line investigation.
Two semen analyses may be required for confirmation. Hormonal profiling, including FSH, LH, testosterone, and prolactin, helps detect endocrine causes. Genetic testing is indicated when suggested by clinical findings.
Ultrasound assists in identifying structural abnormalities. Microbiological testing detects infections requiring treatment. Timely categorization of azoospermia allows appropriate management, whether medical correction, surgical intervention such as varicocelectomy, assisted reproductive techniques including IUI or ICSI, or sperm retrieval procedures like TESE or TESA.
A stepwise laboratory algorithm combined with clinical examination ensures accurate diagnosis and targeted management, improving the likelihood of successful conception.
