Male Infertility: The Complete Guide
How Common Is Male Infertility?
- Male factor is the sole cause in ~30% of infertile couples
- Male factor contributes alongside female factors in another 20–30%
- Only 30–40% of infertility is purely female-factor
A man can appear completely healthy with normal libido and sexual function and still have severely abnormal sperm. The only way to know is a semen analysis.
All Causes of Male Infertility
Testicular causes:
- Varicocele — dilated scrotal veins elevating temperature. Present in 35% of infertile men. Most common correctable cause.
- Cryptorchidism (undescended testicle) — progressive testicular damage if uncorrected
- Orchitis — testicular inflammation from mumps, autoimmune, or bacterial causes
- Cancer treatment — chemotherapy and pelvic radiotherapy are dose-dependently gonadotoxic
Genetic causes:
- Klinefelter syndrome (47,XXY) — most common genetic cause; affects 1 in 650 men; causes azoospermia in most
- Y-chromosome microdeletions (AZFa, AZFb, AZFc) — 5–10% of severe oligospermia
- CFTR mutations — congenital bilateral absence of vas deferens (CBAVD)
Hormonal causes:
- Hypogonadotropic hypogonadism (HH) — pituitary fails to produce FSH/LH. Causes: Kallmann syndrome, prior anabolic steroid use, pituitary tumours. Highly treatable.
- Hyperprolactinaemia — elevated prolactin suppresses HPO axis
- Exogenous testosterone / anabolic steroids — suppress spermatogenesis completely
Obstructive causes:
- Vasectomy (most common obstructive cause)
- Epididymal obstruction from infection
- CBAVD from CFTR mutations
- Ejaculatory duct obstruction
Lifestyle and environmental:
- Smoking, heat exposure, alcohol, cannabis, obesity, pesticides, BPA
Essential Tests
All men: Semen analysis ×2 (4–6 weeks apart); hormonal panel if abnormal (FSH, LH, testosterone, prolactin); physical examination
If severe oligospermia <5M/mL or azoospermia: Peripheral karyotype; Y-chromosome microdeletion analysis; CFTR testing if CBAVD; testicular biopsy
Treatment by Cause
| Cause | Treatment | Success Rate |
|---|---|---|
| Varicocele | Microsurgical varicocelectomy | Improves SA in 60–70% |
| HH | FSH + hCG injections | 70–80% achieve sperm |
| Hyperprolactinaemia | Cabergoline | High response rate |
| Obstructive azoospermia | PESA/TESE + ICSI | >90% retrieval rate |
| Non-obstructive azoospermia | Micro-TESE + ICSI | 40–60% retrieval rate |
| Lifestyle factors | Quit smoking, reduce heat, weight loss | 15–30% improvement |
| Oxidative stress | Antioxidant protocol (3 months) | Modest improvement |
IVF/ICSI for Male Factor
- IUI: For mild oligospermia (TMSC >5–10M)
- IVF with ICSI: TMSC <5M, failed IUI, severe morphology defects, high DFI
- Donor sperm: When no viable sperm can be retrieved or genetic risk is unacceptable
Reference: ASRM 2022 — Male Infertility. EAU 2023 — Male Infertility. WHO 6th edition 2021.
Frequently Asked Questions
What is the most common cause of male infertility?▾
Varicocele is the most common single identifiable and correctable cause — found in 35% of infertile men. Idiopathic oligospermia (no identified cause) is the most common overall category. Among genetic causes, Klinefelter syndrome is most common in azoospermia and Y-chromosome microdeletions in severe oligospermia.
Can male infertility be cured?▾
Many causes are treatable. Varicocele can be surgically corrected. Hypogonadotropic hypogonadism responds well to FSH/hCG treatment. Obstructive azoospermia has >90% sperm retrieval success. Even non-obstructive azoospermia has 40–60% success with micro-TESE. Lifestyle-related oligospermia improves significantly with change. Only severe genetic testicular failure is irreversible — but even then, ICSI with surgically retrieved sperm is often possible.
How long does male infertility treatment take?▾
Timeline varies by cause. Lifestyle changes take 3 months to show effect in semen analysis. Varicocele surgery shows improvement at 3–6 months post-operation. Hormonal treatment for HH takes 6–12 months for sperm to appear. Always retest with a semen analysis 3–4 months after any intervention.