Specialised tests for the male partner

Karyotyping is the gold standard in looking for genetic causes for infertility.

When is this test indicated:

In patients with fertility issues:

• No pregnancy after trying to conceive for a year;
• Unexplained infertility;
• Birth of a child with a malformation syndrome;
• Stillbirth;
• Azoospermia, severe oligoasthenoteratozoospermia, amenorrhoea, early menopause;
• Chromosomal aberrations detected by prenatal diagnosis;
• Confirmed familial chromosomal rearrangements in family members.

In patients with developmental disorders:

• Multiple hereditary abnormalities;
• Clinical evidence for a chromosomal disease;
• Disorders of growth, sex differentiation and development;
• Intellectual deficit and behavioural abnormalities.

This test is recommended for men with non-obstructive azoospermia (NOA) and severe oligoasthenoteratozoospermia, regardless of the presence of other testicular pathologies. The analysis is indicated in men with sperm concentrations below 10 mln/mL.

Microdeletions (submicroscopic loss of genetic material) in the long arm of the Y chromosome are a common cause of male infertility. They are specifically related to impairments of spermatogenesis. Microdeletions of particular interest are those in the AZF-regions (azoospermia factor regions), which include genes of crucial importance to the development and maturation of spermatozoa.

When is the test indicated?

• DNA analysis for Y-chromosome microdeletions is recommended in cases of severe semen analysis abnormalities – microdeletions are found in 10–15% of men with azoospermia (absence of sperm in the ejaculate) when it is not caused by obstructive defects of the seminal ducts and in 5–10% of men with severe oligozoospermia.
• The Y-chromosome microdeletion test has additional value when assisted reproduction techniques are used:
• The presence of Y-chromosome microdeletions can render unsuccessful therapies for improving semen parameters.
• In azoospermic men, confirmed Y-chromosome microdeletions are essential for assessing the potential success of surgical sperm extraction techniques (ТЕSE, MESA, PESA).
• Y-chromosome microdeletions are always passed on to the male offspring, though not always with the exact extent of impairment of spermatogenesis, and semen parameters tend to deteriorate with age. In confirmed Y-chromosome microdeletions, the future sons could manage their reproduction plans more successfully by resorting to semen cryopreservation at an earlier age, when semen parameters are still good.

A venous blood sample is needed for DNA analysis for Y-chromosome microdeletions, preferably not fasting. Results are ready within 1–2 weeks.

CFTR gene mutations screening is highly recommended in infertile men with unilateral or bilateral congenital absence of the sperm ducts. If a CFTR mutation is confirmed in one of the partners, a DNA analysis of the other must be done to assess the risk of passing cystic fibrosis to the offspring.