Genital infections may instigate the production of sperma- totoxic free oxygen radicals. Gonorrhoea and Chlamydia trachomatis can also cause obstruction of the genital tract. Although antibiotic procedures for MAGI might provide improvement in sperm quality, therapy does not necessarily enhance the probability of conception.
Genetic evaluation A substantial number of andrological fertility disorders that used to be described as idiopathic male infertility will, in fact, have a genetic origin. By taking an extensive family history and carrying out karyotype analysis, a number of these disor- ders can be detected. This will not only yield a diagnosis, but also allow for appropriate genetic counselling. The latter may be very important with the advent of intracytoplasmic sperm injection (ICSI), because the fertility disorder and possibly the corresponding genetic defect may be transferred to the offspring.
Chromosomal abnormalities are more common in men with OAT and with azoospermia. The most common sex chromosome abnormality is Klinefelter’s syndrome (47. XXY), which affects around 10% of men diagnosed with azoospermia. Klinefelter’s syndrome is characterised by hypergonadotrophic hypogonadism. Occasionally, a eunu- choid phenotype is found and gynaecomastia is present. Both testicles are very small and present with tubular sclerosis. In around 60% of all patients, testosterone levels decrease with age requiring androgen replacement. Karyotyping is recom- mended in all men who are candidates for ICSI due to OAT.
In men presenting with poor quality semen, chromo- some translocations and deletions can be found, which