[Correlation between the time of application of chorionic gonadotropins and biological variables in the gametes]

The scheduled administration of human chorionic gonadotropin in the ovarian stimulation schemes used in Assisted reproduction has made possible to control the ovulatory phenomenon. In order to know the biological repercussion upon the ovule as to elapsed time from HCG and the time of capture, the protocols of Gametes Laboratory, were reviewed; there were 277 cases with this factor. The capture moment was from 32.88 to 41.06 hours from HCG administration, with an average of 36.8 +/- 1.01 hours. There was no significant statistical correlation with the total amount of captured oocytes, useful oocytes, defective oocytes (atresic, broken, degenerated) segmentation rate and embryonary quality. There was a positive, lineal, statistical correlation with the amount of post-mature oocytes (r = 0.35, p = 0.019) and negative with fertilization rate (r = -0.30, p = < 0.0001), both without a correlation among themselves. It was concluded that prolonged time between HCG exposition more than difficulting oocyte capture, negatively affects oocyte quality with a diminution in its possibility of being fertilized. It must be found the optimal window that permits easily obtaining the larger amount of oocytes with the best possibilities of originating healthy pre-embryos.