The preparation and culture of washed human sperm: A comparison of a suite of protein-free media with media containing human serum albumin

Abstract

Objective: To compare two suites of culture media (one with HSA and one protein-free (PF) supplemented with methylcellulose) for washing human sperm in IVF. Methods: Semen samples (n = 41) underwent parallel density gradient preparation using PF or HSA-supplemented culture medium and subsequent yield, survival, morphology and motility were compared. Results: The PF medium resulted in a significantly higher sperm yield (P < 0.0001), but similar sperm morphology (P = 0.822) and 24-h survival (P = 0.11). There was, however, a lower percentage of progressively motile sperm (P < 0.0001) and a higher proportion of sperm demonstrating non-progressive motility (P < 0.0001) in the PF medium when observed on a Makler Chamber, apparently an artefact as a similar sperm motility index was measured using a Sperm Quality Analyser (P = 0.83). Attachment of sperm in PF medium to the glass chamber reduced with time and any differences had disappeared after 6 min on the counting chamber. Conclusion: These results support the use of PF media supplemented with methylcellulose as an alternative to HSA, although a modification to the manufacturer's protocol of 6-min pre-incubation before assessing sperm motility must be used. Further studies should investigate the function of such sperm prepared in PF medium.

Keywords

• Sperm
• Sperm preparation
• HSA
• Methylcellulose