🔬 Abnormal Semen Analysis — Assessment & Management

The CBAVD-CFTR connection is the most clinically important genetic implication of an abnormal semen analysis that GPs must recognise — congenital bilateral absence of the vas deferens (CBAVD) presents in adults as obstructive azoospermia (normal testicular function and FSH, absent vas deferens on clinical examination, normal volume but absent sperm due to blockage). It is directly caused by mutations in the CFTR gene (the cystic fibrosis gene) — most men with CBAVD carry at least one CFTR variant. The clinical consequence: if a man with CBAVD (and therefore likely CFTR mutation) uses surgical sperm retrieval (PESA) for IVF with a partner who is also a CFTR carrier, there is a 25% risk of having a child with cystic fibrosis. CFTR testing of the affected man, with partner testing and genetic counselling coordinated through the genetics/fertility service, is needed before fertility treatment in CBAVD — the reproductive risk depends on both partners' variants. GPs who find absent vas deferens on examination in a young man presenting with infertility must refer to andrology AND flag CFTR testing.

The repeat semen analysis before clinical decision-making is a fundamental principle that is often bypassed in primary care — semen quality is highly variable between samples from the same individual, with substantial intra-individual variation in sperm concentration. A single abnormal result may not represent the man's average semen quality — it could reflect: a recent febrile illness (fever >38.5°C causes temporary spermatogenic suppression for approximately 3 months — the time for a complete spermatogenic cycle), an inappropriately short or long abstinence period, a technical laboratory error, or incomplete sample collection. NICE NG257 (2026): if the first semen analysis is abnormal, offer a repeat confirmatory test, ideally 3 months after the initial analysis to allow a full cycle of spermatozoa formation — but as soon as possible if azoospermia or severe oligozoospermia is found — before proceeding to further investigations or treatment. GPs who receive a single abnormal result should request a repeat, provide patient education on correct sample collection technique, and advise avoiding febrile illness-related spermatogenic suppression.

The Y chromosome microdeletion testing in severe male infertility is a clinically consequential genetic investigation — Y chromosome microdeletions in the AZFa, AZFb, or AZFc regions are an important cause of non-obstructive azoospermia and very low sperm concentration; NICE NG257 advises testing in idiopathic azoospermia or sperm concentration <1 million/mL. The clinical significance: complete AZFa or AZFb deletions have negligible sperm-retrieval prospects, and surgical sperm retrieval should not be offered in these circumstances; AZFc deletions (the most common) may still permit sperm retrieval. The most important implication: AZF deletions are transmitted on the Y chromosome to any male offspring born via ICSI (intracytoplasmic sperm injection) — a son will carry the same deletion and may be similarly infertile. Genetic counselling before ICSI is mandatory for all couples where the male partner has a Y chromosome microdeletion.

The varicocoele and male infertility relationship is an area of ongoing clinical debate — varicocoele is the most common identifiable cause of male infertility (found in approximately 15% of men in the general population, but in approximately 35-40% of men presenting for primary infertility evaluation). The physiological basis: a left varicocoele impairs testicular thermoregulation (the pampiniform plexus normally cools arterial blood flowing to the testis — venous reflux from the varicocoele warms the testis, impairing spermatogenesis, which requires temperature 2°C below core body temperature) and allows reflux of adrenal venous blood carrying cortisol and other metabolites that impair spermatogenesis. The treatment evidence: individual benefit is uncertain. Treatment is considered for a palpable clinical varicocele (assessed standing and with Valsalva) with abnormal semen parameters, relevant reproductive goals and no more appropriate explanation; subclinical (ultrasound-only) varicoceles should not be treated, grade II–III is not an automatic indication for embolisation, and the choice of microsurgical repair, embolisation or other surgery is specialist-led. NICE NG257 (2026) reversed the CG156 advice not to offer varicocele surgery as a fertility treatment: it now advises considering radiological or surgical treatment of a varicocele detected on clinical examination in men trying to conceive who have reduced semen parameters, taking female fertility factors into account.

The GP couple-centred approach to infertility investigation is the most efficient clinical pathway — male and female partner investigations should be initiated simultaneously, not sequentially (waiting for male results before investigating the female partner or vice versa wastes months). NICE NG257 recommends offering both partners assessment and investigation. The GP primary investigation set: for the male partner — two semen analyses, then scrotal/testicular examination ± testosterone and gonadotrophins if abnormal (USS only if a mass or clinical concern); for the female partner — mid-luteal progesterone (7 days before the expected period), FSH/LH only if cycles are irregular or absent, prolactin and TFTs only when clinically indicated, pelvic ultrasound where locally permitted, and chlamydia testing before uterine instrumentation. Both partners investigated and results collated before reproductive medicine referral optimises the specialist consultation, as the couple can be directed immediately toward the appropriate pathway (IUI, IVF, ICSI, donor sperm, donor oocyte) rather than requiring multiple consultations for further GP investigations.

The micro-TESE (microsurgical testicular sperm extraction) for Klinefelter syndrome represents one of the most significant advances in male infertility treatment — Klinefelter syndrome (47,XXY) was historically considered untreatable from a fertility perspective. However, some men with Klinefelter syndrome have focal areas of spermatogenesis within the testis (areas where X-inactivation allows normal spermatogenic cell function). Micro-TESE uses an operating microscope to identify and selectively biopsy these dilated, vascularised tubules containing active spermatogenesis, while avoiding the fibrotic pale tubules containing only Sertoli cells. The retrieved sperm are then used for ICSI. Predictors of sperm retrieval success in Klinefelter mTESE: younger age (spermatogenesis deteriorates with age — early referral is critical), testosterone above the lower limit of normal, lower FSH levels. GPs who diagnose or suspect Klinefelter syndrome in a young man wishing future paternity should refer promptly to andrology (and avoid starting testosterone without specialist advice) — even if the patient is not currently planning a family, early sperm banking (if any sperm are present) may preserve future options.

The NHS IVF funding inequity across England is a significant patient and GP advocacy issue — the number of NHS-funded IVF cycles offered varies between ICB areas and often differs from NICE NG257 recommendations, and some areas offer very limited NHS-funded IVF. This creates a postcode lottery of fertility care that is explicitly at odds with the principle of equitable NHS access. GPs should: (1) be aware of their local ICS fertility commissioning criteria (available from the ICS website or the local fertility unit); (2) advise couples accurately about what is funded locally vs what requires self-funding; (3) advocate for patients who appear to meet NICE NG257 criteria but are denied on local criteria grounds; (4) signpost to Patient Advisory Liaison Service (PALS) for patients who wish to challenge commissioning decisions. The HFEA (Human Fertilisation and Embryology Authority) website (hfea.gov.uk) provides reliable information on local fertility treatment options and success rates by clinic.

The anabolic steroid-induced azoospermia is an increasingly prevalent cause of male infertility that is frequently not volunteered by patients without direct questioning — anabolic androgenic steroids (testosterone enanthate, nandrolone, stanozolol, oxandrolone, boldenone) are used predominantly by younger gym-going men. Exogenous androgens profoundly suppress the hypothalamic-pituitary-gonadal axis by negative feedback, reducing FSH to near-zero and halting spermatogenesis completely within 3-4 months of use. The semen analysis typically shows: azoospermia or near-azoospermia with normal testicular volume (the testes are not atrophied — they contain normal seminiferous tubules with adequate Sertoli cell function, but no active spermatogenesis due to absent FSH stimulation). Recovery after cessation: most men recover spermatogenesis within 6-18 months, but some have prolonged recovery or permanent azoospermia, particularly long-term heavy users. GPs asking about anabolic steroid use should do so in a non-judgmental way: 'Do you use any supplements, performance-enhancing drugs, or anabolic steroids for training purposes?'

The concurrent investigation of both partners from the outset is one of the most evidence-based yet poorly implemented aspects of UK fertility guidance (NICE NG257, 2026) — in UK primary care the male partner is often investigated later than the female partner. This sequential approach wastes months of the couple's reproductive window, particularly significant where the person trying to become pregnant is aged 36 or over (where ovarian reserve declines rapidly and time-to-pregnancy is a critical variable). The GP implementation: at the first infertility consultation, initiate investigations for BOTH partners simultaneously: SA referral for the male partner + mid-luteal progesterone for the female partner (FSH/LH only if cycles are irregular or absent; chlamydia testing before uterine instrumentation) + pelvic ultrasound where locally permitted. This approach shortens the total investigation time, significantly improving the timeliness of specialist referral.