title: Micro-centrifugation of human spermatozoa: its effect on fertilization of hamster oocytes after micro-insemination spermatozoal transfer.
abstract: Micro-centrifugation (MC) at 6500 r.p.m. (3352 g) has not been used previously for spermatozoal concentration and subsequent fertilization. We investigated MC for micro-insemination spermatozoal transfer (MIST) of human spermatozoa from normal donors into hamster oocytes. MC resulted in reduced penetration of hamster oocytes, both after MIST [77.4% (41/53) versus 87.8% (43/49) for control; NS] and after exposure to zona-free hamster oocytes [60.8% (79/130) versus 72.7% (88/121) for control; P less than 0.05]. However, MIST under the zona resulted in better incorporation of sperm nuclei when compared with zona-free hamster oocytes, for spermatozoa exposed to micro-centrifugation (77.4 versus 60.8%, P less than 0.05) and controls (87.8 versus 72.7%, P less than 0.05). Polyspermy was higher after MIST [22.0% (9/41) versus 13.9% (11/79); NS] for MC+, and [25.6% (11/43) versus 13.6% (12/88); NS] for MC-. We conclude that MC does have a negative, but minimal effect on the fertility of human spermatozoa with respect to hamster oocytes.
authors.affiliation: Department of Obstetrics and Gynaecology, National University of Singapore.
authors.forename: S C
authors.initials: SC
authors.lastname: Ng
authors.forename: T A
authors.initials: TA
authors.lastname: Bongso
authors.forename: H
authors.initials: H
authors.lastname: Sathananthan
authors.forename: V C
authors.initials: VC
authors.lastname: Tok
authors.forename: S S
authors.initials: SS
authors.lastname: Ratnam
mesh_terms: D000818:Animals; D002498:Centrifugation; D006224:Cricetinae; D005260:Female; D005306:Fertilization; D006801:Humans; D007315:Insemination, Artificial / Q000379:methods*; D008297:Male; D008647:Mesocricetus; D009865:Oocytes / Q000502:physiology*; D013094:Spermatozoa / Q000502:physiology*