The Halo Sperm Test examines sperm for DNA fragmentation, or damage. Genetic substances (long spherical DNA strands) are contained in sperm cells, but even sperm that look normal can have damaged DNA fragmentation. The test stains sperm and visually determines the presence or absence of DNA fragmentation based on how the sperm head is stained (see the figure below). A sperm DNA fragmentation percentage (SDF value) of less than 20% (of sperm having fragmentation) considered normal. Fertilizing sperm with damaged DNA may affect embryo development and embryo viability, so if the SDF value is high, good sperm is selected by a special method during micro-insemination. This optional hyaluronic acid mature sperm sorting method is recommended in such a case.
Count over 500
SDF (%) = (fragmented + degenerated) ⁄ total × 100