Sperm centriole disfunction and sperm immotility

The two main causes of complete or nearly complete asthenozoospermia are necrozoospermia (presence of only non-viable spermatozoa) and the different ultrastructural abnormalities of spermatozoa. Ultrastructural alterations may affect also the function of the sperm centrosome, which can result in impaired motility. Because in human the inheritance,of the centrosome is paternal and thus linked to the sperm, morphological or functional alterations of it can also be associated with fertilization abnormalities of the oocyte and cleavage irregularities of the embryo. Most of the cases of asthenozoospermia can be treated efficiently by intracytoplasmic sperm injection (ICSI) using ejaculated sperm (from repeated ejaculation) in combination with hypo-osmotic swelling test (HOST) or using testicular sperm depending on the etiology of the impairment. Replacement of abnormal centriole using donor sperm is a theoretical possibility, but at present it is not an efficient method. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.