Diagnosing male infertilityBMJ 2018; 363 doi: https://doi.org/10.1136/bmj.k3202 (Published 04 October 2018) Cite this as: BMJ 2018;363:k3202
- James Wall, general practitioner1,
- Channa N Jayasena, clinical lead in andrology and, clinical senior lecturer and consultant in reproductive endocrinology2 3
- 1Locum general practice, Manchester, UK
- 2Department of Andrology, Hammersmith Hospital, London, UK
- 3Section of Investigative Medicine, Imperial College London, Hammersmith Hospital, London, UK
- Correspondence to C Jayasena
What you need to know
Men have suboptimal sperm measures in nearly half of all couples presenting with infertility.
Smoking, comorbidities such as obesity and diabetes, drugs, and previous surgeries can cause fertility problems for men.
If semen analysis is abnormal, test follicle stimulating and luteinising hormones and testosterone.
If no sperm are found in the semen, small testes suggest a hormonal or testicular cause, whereas normal sized testes point toward an obstructive problem.
Most patients with confirmed male factor infertility will require specialist referral for further management.
Around 1 in 7 couples in the UK1 seek treatment for infertility when they are unable to conceive, despite regular unprotected intercourse. Male infertility describes any factor in men that may prevent a couple from becoming pregnant. In nearly half of infertility cases, the male partner has suboptimal sperm parameters.23 Some cases of idiopathic infertility may have underlying male aetiology. Both partners need to be assessed for infertility, so the couple should ideally be seen together. In this practice pointer, we discuss a practical approach for non-specialists to diagnose male factor infertility in primary care.
What causes male infertility?
In about a third of patients, no cause is identified.2 The infographic outlines common causes such as hormonal, testicular, or obstructive factors. In a prospective cohort study of 1737 men with infertility, undescended testes (10.7%), genetic abnormalities (7.8%), and obstruction (5.9%) were the most common causes.4 Sixty percent of participants in that study were overweight or obese, which may cause sperm DNA damage and suppress reproductive hormone secretion.5 Genitourinary infection, urological surgery during childhood, and illicit drugs are common and under-recognised causes of male infertility. Varicoceles increase scrotal temperature and reduce testicular perfusion.6 A meta-analysis of observational studies noted that varicoceles were associated with reduced sperm quality.7 Forty percent of men with primary infertility …