Abstract Study question Do the in vitro motility characteristics of sperm collected using a microfluidic device (ZyMot) differ from those by density gradient centrifugation (DGC)? Summary answer ZyMot-collected had longer-lasting than DGC, but head beat-cross frequency was inferior due to absence washing vitro. What is known already ZyMot (DxNow, Inc., USA) can sort highly motile with low react...