title: Recurrent failure of pronucleus formation after intracytoplasmic sperm injection.
abstract: We report on a couple with complete fertilization failure in three consecutive trials of intracytoplasmic sperm injection. Some of the unfertilized oocytes were fixed and decondensed sperm heads were found in all of them. It is not clear whether specific defects of the oocyte, abnormalities of sperm chromatin, or a combination of factors are responsible for the observed failure to develop pronuclei.
mesh_terms: D000328:Adult; D002843:Chromatin / Q000473:pathology; D003593:Cytoplasm / Q000502:physiology*; D005260:Female; D005307:Fertilization in Vitro; D006801:Humans; D007248:Infertility, Male / Q000628:therapy; D008297:Male; D008846:Micromanipulation; D009845:Oligospermia / Q000503:physiopathology; D009865:Oocytes / Q000166:cytology; D013094:Spermatozoa / Q000473:pathology / Q000502:physiology*; D017211:Treatment Failure