MALE INFERTILITY

male infertility
Definition of infertility
Failure of conception after at least 12 months of unprotected intercourse. The chance of a normal couple conceiving is estimated at 20 - 25% per month, 75% by 6 months, and 90% at 1 year.

Epidemiology
Up to 50% of infertility is due to male factors. Up to 25% of couples may be affected at some point in their reproductive years.

Pathophysiology
Failure of fertilization of the normal ovum due to defective sperm development, function, or inadequate numbers. There may be abnormalities of morphology (teratospermia), motility (asthenospermia), low sperm numbers (oligospermia), or absent sperm (azoospermia). Abnormal epididymal function may result in defective spermatozoa maturation or transport, or induce cell death.

Aetiology
- Idiopathic (25%)
- Varicocele (present in 40%)
- Cryptorchidism (undescended testes)
- Functional sperm disorders: immunological infertility (sperm antibodies); head or tail defects;
- Kartagener's syndrome (immotile cilia); dyskinetic cilia syndrome
- Erectile or ejaculatory problems
- Testicular injury: orchitis (post-pubertal, bilateral mumps orchitis); testicular torsion; trauma; radiotherapy
- Endocrine disorders: Kallmann's syndrome (isolated gonadotrophin deficiency causing hypogonadism); Prader - Willi syndrome (hypogonadism, short stature, hyperphagia, obesity); pituitary gland adenoma, radiation, or infection
- Hormone excess: excess prolactin (pituitary tumour); excess androgen (adrenal tumour, congenital adrenal hyperplasia, anabolic steroids); excess oestrogens
- Genetic disorders: Kleinfelter's syndrome (47XXY) involves azoospermia, â?? FSH/LH and â? testosterone; XX male; XYY syndrome
- Male genital tract obstruction: congenital absence of vas deferens; epididymal obstruction or infection; Mullerian prostatic cysts; groin or scrotal surgery
- Systemic disease: renal failure; liver cirrhosis; cystic fibrosis
- Drugs: chemotherapy; alcohol; marijuana; sulphasalazine; smoking
- Environmental factors: pesticides; heavy metals; hot baths

History
- Sexual: duration of problem; frequency and timing of intercourse; previous successful conceptions; previous birth control; erectile or ejaculatory dysfunction.
- Developmental: age at puberty; history of cryptorchidism; gynaecomastia.
- Medical and surgical: detailed assessment for risk factors recent febrile illness; post-pubertal mumps orchitis; varicocele; testicular torsion, trauma, or tumour; sexually transmitted diseases; genitourinary surgery; radiotherapy; respiratory diseases associated with ciliary dysfunction; diabetes.
- Drugs and environmental: previous chemotherapy; exposure to substances which impair spermatogenesis or erectile function; alcohol consumption; smoking habits; hot baths.
- Family: hypogonadism; cryptorchidism. Examination
Perform a full assessment of all systems, with attention to general appearance (evidence of secondary sexual development; signs of hypogonadism; gynaecomastia). Urogenital examination should include assessment of the penis (Peyronie's plaque, phimosis, hypospadias); measurement of testicular consistency, tenderness, and volume with a Prader orchidometer (normal >20ml; varies with race); palpate epididymis (tenderness, swelling) and spermatic cord (vas deferens present or absent, varicocele); digital rectal examination of prostate.

Investigation of male infertility
Basic investigations
- Semen analysis 2 or 3 specimens over several weeks, collected after 2 - 7 days of sexual abstinence. Deliver specimens to the laboratory within 1h. Ejaculate volume, liquefaction time, and pH are noted (Table 12.1). Microscopy techniques measure sperm concentration, total numbers, morphology, and motility. The mixed agglutination reaction (MAR test) is used to detect antisperm antibodies. The presence of leucocytes (>1 Ã 106/ml of semen) suggests infection, and cultures should be requested.
- Hormone measurement Serum FSH, LH, and testosterone. In cases of isolated low testosterone level, it is recommended to test morning and free testosterone levels. Raised prolactin is associated with sexual dysfunction, and may indicate pituitary disease.

Special investigations
Chromosome analysis
Indicated for clinical suspicion of an abnormality (azoospermia or oligospermia, small atrophic testes with â?? FSH).

Testicular biopsy
Performed for azoospermic patients, to differentiate between idiopathic and obstructive causes. May also be used for sperm retrieval.

Sperm function tests
- Post coital test: cervical mucus is taken just before ovulation, and within 8 hours of intercourse, and microscopy performed. Normal results shows >10 sperm per high-powered field, the majority demonstrating progressive motility. Abnormal results indicate inappropriate timing of the test; cervical mucus antisperm antibodies; abnormal semen; inappropriately performed coitus.
- Sperm penetration test: a sample of semen is placed directly onto pre-ovulatory cervical mucus on a slide and the penetrative ability of spermatozoa observed.
- Sperm-cervical mucus test: a specimen of semen (control), and one mixed with cervical mucus are placed separately on a slide, and observed for 30 minutes. More than 25% exhibiting jerking movements in the mixed sample (but not the control) is a positive test for antisperm antibodies.

Imaging
- Scrotal ultrasound scan is used to confirm a varicocele and assess testicular abnormalities.
- Transrectal ultrasound scan is indicated for low ejaculate volumes, to investigate seminal vesicle o
obstruction (>1.5cm width) or absence and ejaculatory duct obstruction (>2.3mm).
- Vasography Vas deferens is punctured at the level of the scrotum and injected with contrast. A normal test shows the passage of contrast along the vas deferens, seminal vesicles, ejaculatory duct, and into the bladder, which rules out obstruction.
- Venography used to diagnose and treat varicoceles (embolization)