Discrimination between nonhyperactivated and classical hyperactivated motility patterns in human spermatozoa using...

Area of Science:

• Reproductive Biology
• Sperm Motility Analysis
• Fertility Research

Background:

• Objective identification of human hyperactivated (HA) sperm motility remains challenging.
• Classical descriptions of HA patterns exist but lack standardized objective criteria.
• Previous methods for HA analysis relied on subjective slow-motion observation.

Purpose of the Study:

• To define new, objective criteria for the automatic identification of human hyperactivated sperm motility.
• To establish criteria for classifying distinct HA patterns.
• To assess the association between objectively identified HA motility and fertilization endpoints.

Main Methods:

• Sperm samples from fertile men were analyzed using Ham's F-10 medium.
• A previously established slow-motion method was used to select 342 sperm representing various motility patterns.
• Automatic sorting for HA was developed using criteria for linearity (≤65), velocity (≥100 microns/s), and head displacement (≥7.5 microns).
• Additional criteria were defined for subclassifying HA patterns.

Main Results:

• New objective criteria were established for automatic sorting of human hyperactivated sperm motility.
• The defined criteria successfully classified non-HA, circling, high-curvature, thrashing, star, and helical patterns.
• The incidence of HA motility, identified by both new and old methods, showed a significant association with multiple fertilization endpoints.

Conclusions:

• The developed objective criteria provide a reliable method for identifying human hyperactivated sperm motility.
• This automated approach enhances consistency and objectivity in HA motility assessment.
• The findings reinforce the significant role of hyperactivated sperm motility in successful fertilization.