Asthenozoospermia

Asthenozoospermia means the proportion of motile sperm, particularly progressively motile sperm, is lower than the reference range on semen analysis. It can occur with an otherwise normal sperm count and morphology, and possible contributors include infection, varicocele, antisperm antibodies, oxidative stress, heat exposure or structural defects of the sperm tail, though often no single cause is identified. Management depends on any identified cause and the degree of reduction; many men with asthenozoospermia go on to conceive naturally or with IUI, IVF or ICSI depending on the overall semen picture and female partner factors.

Also known as: low sperm motility, weak sperm movement

Last reviewed: 9 September 2026. Written by the Antega Editorial Team. General information only — always follow the advice of your own clinic, doctor or pharmacist.