Exposure of human spermatozoa to the cumulus oophorus results in increased relative force as measured by a 760 nm laser optical trap.

Spermatozoa change their movement characteristics in response to different environmental conditions. To investigate the relative force of spermatozoa exhibiting different motility patterns, a laser optical trap was used. A laser beam at 760 nm was directed through a microscope objective and focused above the spermatozoa to create a three-dimensional optical trap.