Nuclear status and cytogenetics of embryos derived from in vitro-matured oocytes.
OBJECTIVE
To analyze embryos after in vitro maturation by investigating their nuclear status and cytogenetic constitution.


METHODS
Prospective randomized laboratory study.


METHODS
Reproductive medicine unit in an academic hospital.


METHODS
Patients with male and tubal factor infertility undergoing fertility treatment.


METHODS
Denuded immature oocytes (n = 75) were matured in vitro for 24-30 hours, and intracytoplasmic sperm injection was performed 30 hours after oocyte retrieval. Fluorescence in situ hybridization was performed on the produced embryos.


METHODS
Blastomere content of the total embryo.


RESULTS
The in vitro-matured oocytes showed a similar fertilization rate as the in vivo-matured oocytes, but with a higher incidence of noncleavage (21.0%). In addition, 26.7% of these embryos arrested at the first mitotic division. Thirty embryos were processed for fluorescence in situ hybridization; only 6.7% had all mononuclear blastomeres, 30.0% had at least one binuclear blastomere, 43.3% had at least one multinuclear blastomere, and 56.6% contained anuclear cells. The chromosomal constitution was analyzed in 14 embryos, and chromosomal anomalies were found in 11 (78.5%).


CONCLUSIONS
Germinal vesicle oocytes retrieved from superovulated patients and cultured in vitro for a short time had the ability to resume meiosis and achieve fertilization. However, arrest of embryo development was common. These embryos showed a high incidence of multinuclear blastomeres and aneuploidy, suggesting abnormal cytokinesis or genetic abnormalities.
Nogueira
D
D
Centre for Reproductive Medicine, University Hospital, Dutch-speaking Brussels Free University (Vrije Universiteit Brussel), Brussels, Belgium. lrianad@az.vub.ac.be
Staessen
C
C
Van de Velde
H
H
Van Steirteghem
A
A
D000328:Adult; D001757:Blastomeres / Q000502:physiology; D002467:Cell Nucleus / Q000473:pathology; D002478:Cells, Cultured; D002869:Chromosome Aberrations; D003582:Cytogenetics / Q000379:methods*; D004622:Embryo, Mammalian / Q000502:physiology*; D005260:Female; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007247:Infertility, Female; D009865:Oocytes / Q000166:cytology / Q000502:physiology*; D011446:Prospective Studies; D011897:Random Allocation; D020554:Sperm Injections, Intracytoplasmic