Table 1. Summary of the clinical and laboratory aspects pertaining to necrozoospermia.
| Testing for necrozoospermia |
|---|
| Indication: if total sperm motility is less than 40% |
| Importance: in order to distinguish whether the immotile spermatozoa are dead (necrozoospermia) or are alive but with abnormal motility (asthenozoospermia), as this will have clinical implications in terms of approach and management |
| Methods: |
| • Eosin-nigrosin staining: dead sperm heads are stained dark pink or red – all tested sperm are damaged and can no longer be used for ART |
| • HOS test: live sperm tails become swollen – sperm is not damaged and can be used for ART |
| Causes and risk factors of necrozoospermia |
| • Genital tract infections – the most common cause |
| • Testicular hyperthermia – local or systemic (such as fever) |
| • Varicocele |
| • Hyperthyroidism |
| • Spinal cord injury |
| • Polycystic kidney disease |
| • Antisperm antibodies |
| • Advanced male age |
| • Toxic substances – such as: tobacco, cannabis, pesticides |
| • Idiopathic |
| Note: Should always rule out false results due to lubricant use or contamination of semen sample with antiseptic solution, soap, or water |
| Management of necrozoospermia |
| • Avoiding and treating underlying risks and conditions |
| • Frequent ejaculation |
| • Absolute asthenozoospermia: consider the diagnosis of flagellar dyskinesia - perform HOS test or use enhancers of sperm motility and select viable sperm for ICSI |
| • Absolute necrozoospermia: consider SDF testing if ejaculated live sperm are to be used in ICSI, testicular sperm extraction followed by ICSI |
ART: assisted reproductive technology, HOS: hypoosmotic swelling, ICSI: intracytoplasmic sperm injection, SDF: sperm DNA fragmentation.