title: Blastocyst development after sperm selection at high magnification is associated with size and number of nuclear vacuoles.
abstract: Spermatozoa selection at high magnification before intracytoplasmic sperm injection seems to be positively associated with pregnancy rates after day 3 embryo transfers. The aim was to demonstrate an association between the presence of vacuoles in sperm nuclei and the competence of embryos to develop to day 5. Grading of spermatozoa at x 6000-x 12,500 magnification: grade I, no vacuoles; grade II, <or=2 small vacuoles; grade III, >or=1 large vacuole; grade IV, large vacuoles with other abnormalities. The outcome of embryo development in a group of 25 patients after sibling oocyte injection with the four different grades of spermatozoa showed no significant difference in embryo quality up to day 3. However, the occurrence of blastocyst formation was 56.3 and 61.4% with grade I and II spermatozoa respectively, compared with 5.1% with grade III and 0% with grade IV respectively (P < 0.001). Spermatozoa selection at high magnification using Nomarski interference contrast is useful to identify more precisely the size and the number of nuclear vacuoles that greatly exert a negative effect on embryo development to the blastocyst stage. These observations confirm previous studies pointing to possible 'early and late paternal effects', both of which may have an impact on early embryonic development.
authors.affiliation: Institute for Reproductive Medicine and Endocrinology, Bregenz, Austria. pierrevdz@hotmail.com
authors.forename: Pierre
authors.initials: P
authors.lastname: Vanderzwalmen
authors.forename: Antje
authors.initials: A
authors.lastname: Hiemer
authors.forename: Paul
authors.initials: P
authors.lastname: Rubner
authors.forename: Magnus
authors.initials: M
authors.lastname: Bach
authors.forename: Anton
authors.initials: A
authors.lastname: Neyer
authors.forename: Astrid
authors.initials: A
authors.lastname: Stecher
authors.forename: Petr
authors.initials: P
authors.lastname: Uher
authors.forename: Martin
authors.initials: M
authors.lastname: Zintz
authors.forename: Bernard
authors.initials: B
authors.lastname: Lejeune
authors.forename: Sabine
authors.initials: S
authors.lastname: Vanderzwalmen
authors.forename: Guy
authors.initials: G
authors.lastname: Cassuto
authors.forename: Nicolas H
authors.initials: NH
authors.lastname: Zech
mesh_terms: D000328:Adult; D001755:Blastocyst / Q000166:cytology*; D002467:Cell Nucleus / Q000648:ultrastructure; D004624:Embryo Transfer; D047108:Embryonic Development; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007248:Infertility, Male / Q000473:pathology / Q000628:therapy; D008297:Male; D011247:Pregnancy; D011256:Pregnancy Outcome; D020554:Sperm Injections, Intracytoplasmic / Q000379:methods; D013094:Spermatozoa / Q000648:ultrastructure*; D014617:Vacuoles / Q000648:ultrastructure