Male Fertility: A Complete Guide
Male factor infertility contributes to approximately 40–50% of all infertility cases, either alone or in combination with female factors. Yet male fertility is often overlooked or evaluated late. A semen analysis is the single most informative initial test.
Understanding Semen Analysis
A semen analysis measures key parameters of sperm health. WHO 2021 reference values (5th centile of fertile men):
| Parameter | WHO 2021 Lower Reference |
|---|---|
| Volume | ≥1.4 mL |
| Sperm concentration | ≥16 million/mL |
| Total sperm count | ≥39 million per ejaculate |
| Total motility | ≥42% |
| Progressive motility | ≥30% |
| Morphology (Kruger strict) | ≥4% normal forms |
| Vitality | ≥54% live |
Understanding Your Results
Oligospermia: Low sperm count (<16 million/mL). Mild oligospermia may respond to treatment; severe oligospermia (<5 million/mL) typically requires ICSI.
Asthenospermia: Low motility (<42% total). Sperm cannot navigate the female reproductive tract effectively. ICSI bypasses motility requirements.
Teratospermia: Abnormal morphology (<4% normal forms by Kruger strict criteria). Most men have largely abnormal forms — Kruger strict criteria are highly sensitive, so isolated teratospermia alone rarely causes infertility if counts and motility are normal.
Azoospermia: No sperm in the ejaculate. Affects 1% of men and 10–15% of infertile men. Two types:
- Obstructive azoospermia (OA): Sperm are produced but cannot reach the ejaculate due to blockage (vas deferens absence, epididymal obstruction). Sperm retrieval (PESA/TESE) is highly successful — ICSI live birth rates comparable to non-azoospermic men.
- Non-obstructive azoospermia (NOA): Testicular failure — sperm production is absent or severely impaired. Micro-TESE can retrieve sperm in approximately 50% of cases.
Causes of Male Infertility
Varicocele — dilated veins in the scrotum — is the most common correctable cause, found in 35% of infertile men. Varicocele repair (varicocelectomy) improves semen parameters in 60–70% of cases and is recommended when semen parameters are abnormal and the female partner has normal fertility (ASRM 2022).
Hormonal causes: Low testosterone, elevated FSH (indicates testicular failure), elevated prolactin (pituitary adenoma), thyroid disorders.
Genetic causes: Y-chromosome microdeletions (AZFa, AZFb, AZFc regions) — found in 5–10% of severe oligospermic men. Klinefelter syndrome (47,XXY) — most common genetic cause of azoospermia. Genetic testing is recommended before TESE/ICSI.
Lifestyle factors: Smoking reduces sperm concentration and motility by 15–20%. Heat exposure (laptop on lap, hot baths, tight underwear) raises scrotal temperature and impairs spermatogenesis. Anabolic steroids suppress the HPO axis and cause azoospermia. Cannabis and heavy alcohol reduce testosterone and sperm quality.
Infections: Chlamydia, gonorrhoea, and mumps orchitis can cause irreversible testicular damage. Subclinical genital tract infections cause DNA fragmentation.
DNA Fragmentation: Sperm DNA fragmentation index (DFI) measures genetic damage within sperm. DFI >25% is associated with recurrent miscarriage and poor IVF outcomes. Lifestyle modification and antioxidant supplementation can reduce DFI by 20–30%.
Treatment Options
| Condition | Treatment |
|---|---|
| Mild oligospermia | Lifestyle optimisation, antioxidants, IUI |
| Moderate oligospermia | IUI (2–3 cycles), then IVF/ICSI |
| Severe oligospermia (<5M/mL) | IVF with ICSI |
| Obstructive azoospermia | PESA/TESE + ICSI |
| Non-obstructive azoospermia | Micro-TESE + ICSI (if sperm retrieved) |
| Varicocele with abnormal SA | Varicocelectomy or IVF/ICSI |
| Hormonal imbalance | Medical treatment (clomiphene, FSH injections) |
Optimising Sperm Health
Per ASRM 2022 lifestyle recommendations:
- Antioxidants: Vitamin C (1g/day), Vitamin E (400IU/day), Zinc (66mg/day), CoQ10 (200–400mg/day), Selenium, L-carnitine — 3 months minimum (one spermatogenesis cycle = 74 days)
- Temperature: Avoid hot baths, saunas, and laptop heat on lap
- Exercise: Regular moderate exercise improves sperm quality; extreme endurance exercise may worsen it
- BMI: Both underweight and overweight men have significantly lower sperm concentrations
- Cycle of spermatogenesis: Takes 72–74 days — allow 3 months for any intervention to show effect
Reference: WHO Laboratory Manual for Semen Analysis, 6th edition 2021. ASRM Practice Committee — Evaluation of the Azoospermic Male, 2022.
Frequently Asked Questions
What is a normal sperm count for fertility?▾
Per WHO 2021 guidelines, a normal sperm concentration is ≥16 million per mL, or ≥39 million sperm per ejaculate. However, sperm count is only one factor — motility, morphology, and DNA integrity also matter significantly for fertility.
Can a man with zero sperm count (azoospermia) father a child?▾
Yes, in many cases. Obstructive azoospermia (where sperm are produced but cannot exit) allows sperm retrieval via PESA or TESE with very high success rates. Non-obstructive azoospermia is more challenging, but micro-TESE retrieves sperm in approximately 50% of cases, which is then used for ICSI.
How long does it take to improve sperm quality?▾
Spermatogenesis (sperm production) takes 72–74 days. Any lifestyle change or treatment will take at least 3 months to show improvement in semen parameters. Antioxidant supplementation, quitting smoking, and reducing heat exposure are the most evidence-based approaches.
Is ICSI always needed for male factor infertility?▾
Not always. Mild oligospermia or asthenospermia may respond to IUI (intrauterine insemination) if sperm counts are sufficient (>5–10 million total motile sperm). ICSI is recommended for severe oligospermia (<5M/mL), azoospermia requiring surgical retrieval, or failed IVF fertilisation.