From the Guidelines
Elevated FSH is a significant indicator of male infertility, particularly when associated with azoospermia, oligozoospermia, or testicular atrophy, as it suggests impaired sperm production 1.
Definition and Causes
Elevated FSH levels in men typically indicate a problem with sperm production in the testes. This occurs because the pituitary gland increases FSH production when it detects insufficient feedback from the testes, essentially trying to stimulate more sperm production. Common causes of elevated FSH in men include primary testicular failure, Klinefelter syndrome, prior trauma or surgery, varicocele, or genetic disorders affecting the testes.
Diagnosis and Treatment
Normal FSH levels in adult men typically range from 1.5-12.4 mIU/mL, though reference ranges may vary slightly between laboratories. If a man has elevated FSH and is experiencing fertility issues, he should consult with a reproductive endocrinologist or urologist specializing in male fertility.
- Clinicians should recommend karyotype testing for males with primary infertility and azoospermia or sperm concentration <5 million sperm/mL when accompanied by elevated FSH, testicular atrophy, or a diagnosis of impaired sperm production 1.
- Treatment approaches depend on the underlying cause but may include assisted reproductive technologies like intracytoplasmic sperm injection (ICSI) if some sperm are present, or in severe cases, consideration of donor sperm.
- Lifestyle modifications such as avoiding excessive heat to the testes, limiting alcohol consumption, and maintaining healthy weight can also support overall reproductive health.
Clinical Significance
The results from semen analysis (SA) should be used to guide management of the patient 1. In general, results are of greatest clinical significance when multiple SA abnormalities are present. Clinicians should obtain hormonal evaluation including follicle-stimulating hormone (FSH) and testosterone for infertile men with impaired libido, erectile dysfunction, oligozoospermia 1. It is crucial to address elevated FSH levels and associated infertility issues promptly to improve the chances of successful fertility treatment and overall reproductive health 1.
From the Research
Relationship Between Elevated FSH and Male Infertility
- Elevated FSH levels are associated with abnormal spermatogenesis and may indicate primary testicular failure 2, 3, 4.
- Studies have shown that FSH levels above 4.5 IU/L are associated with abnormal semen analysis, including impaired sperm morphology and concentration 2, 3.
- The range for 'normal' FSH varies between institutions, but a level above 4.8 IU/L has been found to be abnormal in male infertility cases 3.
- Elevated FSH serum levels correlate with the appearance of Sertoli cell only tubules, which can indicate severe derangement of spermatogenesis 4.
Diagnostic Significance of FSH in Male Infertility
- FSH helps to differentiate between obstruction or spermatogenetic dysfunction as the possible cause of azoospermia 4.
- Serum FSH levels can be used to predict male factor infertility in patients with a borderline high FSH level and a low testosterone level 2.
- FSH values lower than those currently considered normal may be associated with abnormal semen analysis, suggesting that the 'normal' range for FSH may need to be reconsidered 2.
Treatment of Male Infertility with FSH
- FSH administration has been shown to be effective in treating male idiopathic infertility, with a significant increase in sperm concentration and normozoospermia 5.
- FSH treatment can lead to pregnancy in one out of four patients with idiopathic infertility, with higher sperm concentrations and progressive sperm motility found in the pregnancy group 5.
- New compounds, such as allosteric ligands and chimeric gonadotropins, may represent interesting avenues for future personalized, pharmacological approaches to male infertility 6.