Male Infertility: Causes, Diagnosis and Advanced Treatment Options

For conception to occur naturally, a man must produce adequate numbers of healthy sperm, the sperm must be properly formed and capable of forward swimming motion, the sperm must travel unobstructed from the testes through the reproductive tract, and they must successfully penetrate and fertilise the egg. Problems at any point in this chain can cause or contribute to infertility.

Sperm are produced in the testes through a process called spermatogenesis that takes approximately 74 days. Each sperm consists of a head containing the genetic material, a midpiece providing energy, and a tail enabling movement. Sperm quality is assessed through semen analysis, which evaluates count, motility, morphology, and other parameters. However, standard semen analysis has limitations and does not capture all dimensions of sperm health, particularly DNA integrity.

Primary male infertility refers to men who have never fathered a child. Secondary male infertility refers to men who have previously fathered children but are now experiencing difficulty. Both are valid medical presentations requiring investigation. Sperm quality can change significantly over time due to age, illness, lifestyle changes, medications, or new medical conditions, so a previous normal result does not rule out a current problem.

A varicocele is an abnormal enlargement of the veins within the scrotum, similar to varicose veins in the legs. It is the single most common correctable cause of male infertility, found in 15 to 20 percent of all men and in 35 to 40 percent of men investigated for infertility. Varicoceles impair fertility by raising the temperature inside the scrotum, disrupting blood flow to the testes, and creating an accumulation of toxic metabolites. These effects damage sperm production and quality across all parameters: count, motility, and morphology.

Not all varicoceles require treatment. Clinical varicoceles associated with abnormal semen parameters in a couple with infertility are the primary indication for varicocele repair (varicocelectomy). Surgical or radiological repair can significantly improve semen parameters and restore natural fertility or improve IVF outcomes in properly selected patients.

Azoospermia is the complete absence of sperm in the ejaculate and is found in approximately 1 percent of all men and 10 to 15 percent of infertile men. It is classified into two main types, each with different causes and treatment implications.

The foundational test. Evaluates sperm count, motility, morphology, volume, liquefaction, and pH based on WHO 2021 reference criteria. Sample produced after 2 to 5 days of abstinence.

Measures percentage of sperm with damaged DNA. Recommended for unexplained infertility, recurrent miscarriage, and repeated IVF failure with apparently normal semen parameters.

FSH, LH, testosterone, prolactin, and TSH. Distinguishes hormonal from primary testicular causes and identifies treatable hormonal abnormalities.

Identifies varicoceles, testicular masses, absent or obstructed vas deferens, and epididymal abnormalities. Essential when physical examination is abnormal or semen parameters are significantly reduced.

Chromosomal karyotype, Y-chromosome microdeletion analysis, and CFTR mutation testing for CBAVD. Recommended for azoospermia, severe oligospermia (below 5 million per mL), or recurrent miscarriage.

For men with very low ejaculate volume and suspected retrograde ejaculation. Confirms presence of sperm in urine after orgasm.

For azoospermic men. Determines whether sperm production is occurring and whether sperm can be retrieved for IVF-ICSI.

For many men, targeted lifestyle changes produce meaningful improvements in semen parameters within 3 months (one full cycle of spermatogenesis). Cessation of smoking, reducing alcohol, stopping anabolic steroids, weight loss in overweight men, reducing scrotal heat exposure, correcting nutritional deficiencies, and antioxidant supplementation are all evidence-based first steps. For men with mild semen abnormalities and no identifiable medical cause, a 3-month lifestyle optimisation period is worthwhile before proceeding to assisted reproduction.

Hormonal causes of male infertility are highly treatable. Hypogonadotrophic hypogonadism responds well to gonadotrophin injections (FSH and hCG), which stimulate the testes to produce sperm. Hyperprolactinaemia is treated with cabergoline or bromocriptine, often restoring normal sperm production. Thyroid disorders are managed with appropriate medication. Infections are treated with antibiotics, though damage from previous infections may be permanent.

Varicocelectomy is performed microsurgically (microsurgical subinguinal varicocelectomy), which is associated with lower recurrence and complication rates. Studies consistently show improvement in sperm count, motility, and morphology in approximately 60 to 70 percent of men following repair. Some men recover sufficient sperm parameters for natural conception or IUI. For others, improved sperm quality translates to better IVF-ICSI outcomes. The decision to proceed with varicocelectomy versus direct IVF-ICSI depends on semen parameters, female partner factors, and duration of infertility.

IUI is appropriate for mild male factor infertility where the total motile sperm count after preparation is sufficient (generally above 5 to 10 million). Prepared sperm are placed directly into the uterus at ovulation, increasing the concentration of sperm near the egg. IUI suits well-selected couples; your doctor will explain what to expect. IUI is typically tried for 3 to 6 cycles before advancing to IVF if pregnancy has not occurred.

ICSI is the cornerstone of advanced male infertility treatment. A single sperm is selected by the embryologist and injected directly into each mature egg, bypassing all natural barriers to fertilisation. ICSI achieves fertilisation rates of 70 to 85 percent per egg and is used for severe oligospermia, poor motility, significant teratospermia, previous IVF fertilisation failure, and all cases of surgically retrieved sperm. It has transformed the prognosis for severe male factor infertility, giving men who would previously have had no options a realistic path to biological fatherhood.

For men with azoospermia or very severe oligospermia, sperm can be retrieved surgically and used immediately with ICSI or frozen for future use.

(Percutaneous Epididymal Sperm Aspiration): Fine needle aspiration of the epididymis under local or light sedation. Used for obstructive azoospermia. Simple, minimally invasive, highly effective for men with CBAVD or post-vasectomy obstruction.

(Testicular Sperm Aspiration): Fine needle aspiration directly from the testis. Used when PESA does not yield sperm or for testicular sperm retrieval.

(Microsurgical Testicular Sperm Extraction): The most advanced technique for non-obstructive azoospermia. The surgeon uses an operating microscope to identify and sample areas of the testis most likely to contain sperm production. Successful sperm retrieval in 50 to 60 percent of men with NOA including Klinefelter syndrome.

(Microsurgical Epididymal Sperm Aspiration): Open microsurgical aspiration of the epididymis, yielding larger numbers of sperm suitable for freezing multiple vials for future use.

Men who underwent vasectomy and now wish to father children have two options: vasectomy reversal (vasovasostomy or vasoepididymostomy) to restore natural sperm flow, or PESA or TESA to retrieve sperm for IVF-ICSI. The choice depends on time since vasectomy, female partner age and fertility, and cost considerations. Vasectomy reversal success is inversely related to the time elapsed since vasectomy.

When sperm retrieval is not possible or when genetic testing reveals conditions that carry significant risk of transmission, donor sperm from a certified sperm bank is a highly effective alternative. Donor sperm is screened thoroughly for infectious diseases, genetic conditions, and health history. It works in the same way as partner sperm of comparable quality for the same procedures.