[First polar body morphology and fertilization rate, cleavage rate, and embryo quality].
OBJECTIVE
to determine the relationship between the morphology of the first spindle pole of human oocytes and rates of fertilization, fragmentation and embryo quality in procedures of Intracytoplasmic Sperm Injection (ICSI).


METHODS
retrospective study of 582 consecutive ICSI cycles, from July 2003 to July 2005. The morphology of the first spindle pole (SP) was assessed through the analysis of 3,177 oocytes in metaphase II, immediately before the ICSI procedure, always by the same observer. SP has been classified in the following categories: normal size intact, fragmented or augmented SP. Fertilization rate and fragmentation, and the number and rate of good quality embryos in each one of the three groups studied have been evaluated, 48 hours after ICSI (D2). Embryos with four cells, without fragmentation and with symmetric blastomeres in D2 were considered as of good quality.


RESULTS
rates of fertilization, fragmentation and of good quality embryo formation, resulting from oocyte insemination, with augmented SP (20.7, 16.7 and 5% respectively) were significantly lower than the ones from intact and normal size SP (70.8, 62.5 and 19%, respectively) or from fragmented SP oocytes (69.7, 60.5 and 17.1%, respectively).


CONCLUSIONS
it has been observed that the presence of augmented first spindle pole is related to worse rates of fertilization, fragmentation and bad quality embryo formation. Nevertheless, fragmentation in the first spindle pole of the oocyte does not seem to affect ICSI results.
Picinato
Maria Cristina
MC
Setor de Reprodução Humana, Departamento de Ginecologia e Obstetrícia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brasil. picinato@fmrp.usp.br
Araújo
Medeiros de
Md
Araújo
Carlos Henrique Medeiros de
CH
Rocha
Marcelo Gondim
MG
Martins
Wellington de Paula
Wde P
Reis
Rosana Maria dos
RM
Ferriani
Rui Alberto
RA
Albuquerque
Paula Andrea de
PA
Navarro
Salles
S
D002970:Cleavage Stage, Ovum; D004622:Embryo, Mammalian; D005306:Fertilization / Q000502:physiology*; D006801:Humans; D012189:Retrospective Studies; D020554:Sperm Injections, Intracytoplasmic / Q000592:standards*; D013997:Time Factors; D015053:Zygote / Q000166:cytology* / Q000648:ultrastructure