How is sperm quality checked for Intracytoplasmic Sperm Injection (ICSI) in In Vitro Fertilization (IVF)?

Sperm Quality Assessment for IVF with ICSI

For IVF with ICSI, sperm quality is assessed through specialized selection techniques that evaluate morphology, motility, and DNA integrity, with the most viable single sperm being selected for direct injection into the egg. 1

Basic Semen Analysis Parameters

• Initial evaluation includes standard semen parameters: volume, concentration, total sperm count, motility, and morphology according to WHO reference values 2, 1
• For men with abnormal parameters on first analysis, a second confirmatory semen analysis should be performed at least one month later 2
• Total Motile Sperm Count (TMSC) is a critical parameter, with values below 10 million indicating potential need for ICSI rather than conventional IVF 2
• Sperm morphology with a threshold value of 4% normal forms is an important predictor of fertilization potential 2

Advanced Sperm Selection for ICSI

• Sperm preparation follows WHO manual guidelines using techniques such as simple wash, swim-up, or density gradient centrifugation to isolate the most viable sperm 2, 1
• For ICSI specifically, individual sperm are evaluated under high magnification (400-1000x) for:
  • Normal head shape and size
  • Absence of vacuoles in the head
  • Normal midpiece and tail 3
• Specialized techniques for challenging cases include:
  • Intracytoplasmic Morphologically Selected Sperm Injection (IMSI) - using 6000x magnification to detect subtle morphological defects 3
  • Hyaluronic acid binding assay - mature sperm can bind to hyaluronic acid, indicating better DNA integrity 3, 1
  • Annexin V binding - to identify non-apoptotic sperm 3

Sperm Function and DNA Integrity Testing

• Sperm DNA fragmentation testing may be considered in cases of recurrent IVF failure or pregnancy loss 2
• For men with high DNA fragmentation, testicular sperm extraction may be considered as testicular sperm typically has lower DNA fragmentation levels than ejaculated sperm 2
• Sperm-zona pellucida binding tests can provide information about sperm fertilizing ability, though these are not routinely performed 4

Special Considerations for Challenging Cases

• For men with total sperm immotility, additional techniques are employed:
  • Hypo-osmotic swelling test (HOST) to identify viable but immotile sperm 3
  • Methylxanthines or pentoxifylline can be used to stimulate motility 3
  • Laser-assisted immotile sperm selection in extreme cases 3
• For severe oligozoospermia (sperm concentration <5 million/mL), ICSI is the recommended approach rather than conventional IVF 5, 6

Common Pitfalls to Avoid

• Relying solely on conventional semen analysis without advanced sperm function testing may miss subtle sperm defects that affect fertilization 4
• Improper collection technique, inadequate abstinence period, or delayed analysis can significantly affect results 1
• Over-reliance on a single parameter rather than considering the complete sperm profile can lead to inaccurate assessment of fertility potential 1
• Failing to consider the specific requirements of ICSI versus conventional IVF - ICSI bypasses many natural sperm functions but still requires careful selection of structurally normal sperm 6

By following these comprehensive assessment protocols, fertility specialists can select the most viable individual sperm for ICSI, optimizing the chances of successful fertilization and healthy embryo development.