Sperm selection before intracytoplasmic sperm injection

In assisted reproduction techniques (ART), the success of embryo development depends mostly on the quality of gametes, and pregnancy outcome is strictly related to both the oocyte and the fertilizing sperm quality. Therefore, during ART, it is mandatory to select a mature and viable sperm with high DNA integrity. Routine sperm preparation and selection in ART is based on density gradient centrifugation or motility. However, it is becoming increasingly clear that new and more rigorous procedures should be considered to recover those sperm able to properly support fertilization, embryo development and birth of healthy babies.