[Sperm selection in assisted reproductive technology: an update].

Sperm selection plays an important role in assisted reproductive technology. In recent years, sperm evaluation is not limited to the assessment of sperm motility and morphology, but involves more other sperm characteristics such as sperm ultrastructure, DNA integrity, apoptosis and membrane. Assessment based on these characteristics is becoming the aim of sperm selection. This article gives an overview on several newly developed techniques for sperm selection according to different technical principles, such as electrophoretic separation, zeta potential, HA binding, Annexin V binding, intracytoplasmic morphologically selected sperm injection (IMSI) and microfluidic sperm sorter, which have all been applied to IVF or ICSI with the exception of microfluidic sperm sorter. It also introduces the advantages, disadvantages and application effects of these techniques.