Morphologic indicators predict the stage of chromatin condensation of human germinal vesicle oocytes recovered from stimulated cycles.
OBJECTIVE
To assess germinal vesicles (GV) recovered from stimulated cycles by means of morphometric and morphologic examination (using contrast-phase and image analysis) and chromatin configuration (using fluorescent DNA imaging), and to evaluate the relevance of morphometric and morphologic parameters as forecasters of chromatin status.


METHODS
Experimental study.


METHODS
University-affiliated infertility clinic.


METHODS
One hundred and thirty-one GV oocytes donated to patients for intracytoplasmic sperm injection.


METHODS
We evaluated 131 GVs by means of morphology and morphometry with the use of contrast phase microscopy. They were subsequently fixed, DNA stained, and assessed by fluorescent microscopy. Compiled data were retrospectively grouped according to three models.


METHODS
Model A: ova were grouped according to chromatin condensation (noncondensed vs. condensed). Model B: ova were grouped according to chromatin distribution in relation to the nucleolus-like body (NLB) (not surrounding vs. surrounding and/or absent) but regardless of the condensation stage. Model C: GV oocytes were grouped according to the combination of both of the previously mentioned parameters (chromatin condensation and distribution in relation to the NLB).


RESULTS
According to the GV classification of model A, nucleoplasm, nucleus position, nuclear envelope continuity, and oocyte size were shown to be relevant and were included in a mathematical model for predicting chromatin condensation stage.


CONCLUSIONS
Noninvasive analysis of GV oocytes using contrast-phase microscopy maintains oocytes in a viable state and allows the chromatin condensation status to be predicted.
Escrich
Laura
L
Valencia University Institute of IVI, Valencia, Spain.
Grau
Noelia
N
Meseguer
Marcos
M
Pellicer
Antonio
A
Escribá
María-José
MJ
D000293:Adolescent; D000328:Adult; D002467:Cell Nucleus / Q000502:physiology* / Q000648:ultrastructure; D002843:Chromatin / Q000502:physiology* / Q000648:ultrastructure; D005260:Female; D006801:Humans; D008856:Microscopy, Fluorescence; D008858:Microscopy, Phase-Contrast; D009685:Nuclear Envelope / Q000648:ultrastructure; D009865:Oocytes / Q000648:ultrastructure*; D006080:Ovarian Follicle / Q000502:physiology; D010062:Ovulation Induction; D020554:Sperm Injections, Intracytoplasmic
D002843:Chromatin