Male Infertility — Causes, Semen Analysis, Diagnosis & Treatment Guide — Symptoms, Causes & Treatment | MyMedicPlus

Male infertility is defined as the inability of a male to cause pregnancy in a fertile female partner after 12 months of regular unprotected intercourse. Male factors contribute to approximately 40-50% of all infertility cases worldwide, either as a sole cause or in combination with female factors. Despite this, male infertility remains under-investigated and under-treated in many healthcare systems, where evaluation often focuses primarily on the female partner. In the UK, approximately 1 in 20 men has a low sperm count and 1 in 100 has no sperm at all (azoospermia). The majority of male infertility cases result from abnormal semen parameters — reduced count (oligospermia), motility (asthenospermia), or morphology (teratospermia). With modern assisted reproductive technologies including ICSI and surgical sperm retrieval, the majority of men with male factor infertility can father biological children.

Pre-testicular (endocrine) causes: hypogonadotropic hypogonadism (low FSH/LH — Kallmann syndrome, pituitary tumour, hyperprolactinaemia, steroid abuse), which impairs spermatogenesis through inadequate gonadotropin stimulation. Testicular causes (most common — 65-80%): varicocele (most common correctable cause, found in 40% of infertile men — venous congestion elevates testicular temperature impairing spermatogenesis); Klinefelter syndrome (47,XXY — most common genetic cause of primary hypogonadism); cryptorchidism (undescended testes — persistent testicular maldescent damages spermatogenesis); orchitis (mumps, sexually transmitted); testicular torsion; cancer therapy (chemotherapy/radiation — gonadotoxic; sperm cryopreservation before treatment is essential); Y chromosome microdeletions (AZF region deletions — found in 10-15% of azoospermic men). Post-testicular (obstructive) causes: congenital bilateral absence of vas deferens (CBAVD — associated with CFTR mutations; all men with CBAVD should have CFTR genetic testing), epididymal obstruction, vasectomy. Lifestyle factors: anabolic steroid abuse (suppresses gonadotropins — a major increasing cause), smoking, alcohol, obesity, recreational drug use, heat exposure.

Male infertility is largely asymptomatic — the primary presenting complaint is the inability to conceive. Physical examination may reveal: varicocele (dilated tortuous veins in the pampiniform plexus, best detected in the standing position — feels like a 'bag of worms'; associated with testicular atrophy on the affected side), small firm testes (Klinefelter syndrome), absent vas deferens on palpation (CBAVD), or sparse body hair and gynaecomastia (hypogonadism). Ejaculatory dysfunction: anejaculation, retrograde ejaculation (semen expelled into bladder — diagnosed by post-ejaculate urine analysis; associated with diabetes, retroperitoneal surgery, or alpha-blocker use), or erectile dysfunction. Significant systemic illness contributing to infertility: symptoms of chronic illness, endocrinopathy (hypothyroidism, Cushing's syndrome, diabetes), or prior cancer treatment. Genetic causes: Klinefelter syndrome may present with delayed puberty, tall stature, and gynaecomastia in adolescence.

Semen analysis is the cornerstone investigation — performed after 2-5 days of abstinence on two separate occasions (WHO 2010 reference ranges): volume above 1.5 mL, total sperm count above 39 million per ejaculate, concentration above 16 million/mL, progressive motility above 30%, total motility above 40%, morphology (Kruger strict criteria) above 4% normal forms. Hormone profile (when indicated — oligospermia, azoospermia, clinical hypogonadism): FSH, LH, total testosterone (ideally morning fasting sample), prolactin, and inhibin B. Elevated FSH indicates primary testicular failure; low FSH suggests hypothalamic/pituitary cause. Genetic testing: karyotype (Klinefelter — 47,XXY; chromosomal abnormalities); Y chromosome microdeletion analysis (AZFa, AZFb, AZFc deletions — critical for guiding prognosis of sperm retrieval); CFTR mutation analysis for CBAVD. Scrotal and transrectal ultrasound: varicocele assessment, testicular volume, epididymal dilation (obstruction). Testicular biopsy: distinguishes obstructive from non-obstructive azoospermia — essential before surgical sperm retrieval.

Varicocele repair: microsurgical subinguinal varicocelectomy is the most effective approach — improves semen parameters in 40-70% of men and may enable natural conception; recommended when varicocele is palpable, associated with abnormal semen parameters, and the female partner has no or age-appropriate infertility factors. Hormonal therapy: gonadotropin injections (hCG + FSH — Pregnyl, Menopur) for hypogonadotropic hypogonadism — highly effective at restoring sperm production (60-90% achieve sperm in ejaculate); clomifene citrate (SERM) for borderline low testosterone with suboptimal spermatogenesis. Assisted reproduction: intrauterine insemination (IUI) with washed sperm for mild male factor; intracytoplasmic sperm injection (ICSI) — injection of a single sperm directly into the egg — effective for severe oligospermia, asthenospermia, or teratospermia with fertilisation rates of 60-80%. Surgical sperm retrieval: percutaneous epididymal sperm aspiration (PESA) or testicular sperm extraction (TESE/micro-TESE) for obstructive or non-obstructive azoospermia — micro-TESE retrieves sperm in 50-60% of non-obstructive azoospermia for ICSI. Azoospermia with complete AZFa/AZFb deletions: no sperm retrieval possible — donor sperm or adoption.

Male infertility causes profound psychological complications — depression affects approximately 50% of men with infertility, with grief, shame, and identity concerns impacting quality of life significantly. Relationship strain and sexual dysfunction are common secondary consequences of infertility investigations and treatment cycles. Untreated or inadequately evaluated oligospermia or azoospermia may mask serious underlying conditions: non-obstructive azoospermia is associated with a 10-fold increased risk of testicular cancer — testicular biopsy may reveal carcinoma in situ (GCNIS); abnormal semen parameters in young men warrant ultrasound examination of the testes. Y-chromosome microdeletion in AZF regions predicts severe oligospermia or azoospermia — AZFa and AZFb deletions indicate no sperm recovery probability with surgical sperm extraction, avoiding unnecessary procedures; AZFc deletions allow sperm recovery in 50-70% of cases. Klinefelter syndrome (47,XXY) causing azoospermia carries systemic risks including osteoporosis, type 2 diabetes, cardiovascular disease, autoimmune conditions, and breast cancer — requiring holistic management beyond fertility. Varicocele, a treatable cause of infertility and reduced testosterone, causes progressive testicular damage if untreated — venous stasis impairs spermatogenesis and Leydig cell function. Failure of infertility workup to identify a cause means the underlying pathology (cryptorchidism, genetic abnormality, environmental exposure) may remain unaddressed. Assisted reproductive technologies carry risks including multiple pregnancy (twins/triplets), ovarian hyperstimulation syndrome in the female partner, and potential genetic transmission of paternal infertility causes to male offspring.

Sperm cryopreservation before cancer treatment is essential — discuss with the oncology team before starting chemotherapy or radiotherapy. Adolescents with undescended testes should undergo orchidopexy by age 12-18 months to maximise fertility potential. Avoid anabolic steroids — the most preventable iatrogenic cause of severe male infertility. Spermatogenesis can take 6-12 months to recover after steroid cessation; some men develop permanent azoospermia. Smoking cessation improves semen parameters. Achieve and maintain healthy weight — obesity reduces testosterone and sperm quality. Avoid prolonged heat exposure to the scrotum (hot baths, saunas, tight underwear, laptop use on lap). Promptly treat genital infections (sexually transmitted infections) to prevent epididymal scarring and obstruction. Mumps vaccination prevents orchitis, which can cause testicular atrophy. Seek fertility assessment after 12 months of trying (or sooner if risk factors are present).

Seek urgent medical attention for sudden onset testicular pain (testicular torsion — a surgical emergency requiring orchidopexy within 6 hours to prevent testicular loss) or a new testicular lump (must be assessed to exclude testicular cancer — the most common cancer in men aged 15-45). Seek a fertility assessment after 12 months of unprotected intercourse without conception, or sooner if you have: a history of undescended testes, chemotherapy or radiotherapy, urogenital surgery, significant scrotal injury, or known genetic conditions. A urologist or andrologist should be consulted for semen analysis and hormonal evaluation. Do not wait and assume infertility is only a female issue — male factor investigation should begin simultaneously with female partner assessment.