Male Infertility

Male infertility is the inability to achieve conception after 12 months of regular, unprotected sexual intercourse due to abnormalities in sperm production, function, or delivery.

Definition

Male infertility is the inability to achieve conception after 12 months of regular, unprotected sexual intercourse due to abnormalities in sperm production, function, or delivery.

Epidemiology

Accounts for approximately 40–50% of infertility cases in couples
Prevalence increases with age, obesity, and lifestyle factors
Varies globally depending on environmental and genetic factors
Commonly underreported due to social stigma
Associated with chronic medical conditions such as diabetes and varicocele
Significant psychosocial impact on affected men and couples
Incidence rising with increasing prevalence of environmental and lifestyle risk factors

Etiology

Pre-testicular: hormonal disorders affecting hypothalamic-pituitary-gonadal axis (e.g., hypogonadism)
Testicular: genetic abnormalities, varicocele, cryptorchidism, infections (mumps orchitis), trauma
Post-testicular: obstruction of sperm transport (e.g., vas deferens obstruction, ejaculatory duct obstruction)
Lifestyle factors: smoking, alcohol, obesity, drug use, heat exposure
Medications: chemotherapy, radiotherapy, anabolic steroids
Systemic illnesses: diabetes, chronic kidney disease, liver disease
Idiopathic in up to 30% of cases

Pathophysiology

Defective spermatogenesis leading to low sperm count (oligospermia) or absence of sperm (azoospermia)
Abnormal sperm morphology or motility (teratozoospermia, asthenozoospermia)
Hormonal imbalances affecting testosterone, FSH, and LH levels
Obstruction of sperm transport preventing delivery to ejaculate
Immunologic causes such as antisperm antibodies
DNA fragmentation in sperm affecting fertilization potential
Chronic systemic conditions impairing testicular function or sperm maturation