Studies of in vitro fertilization using mouse have direct implications to human in vitro fertilization pro-gram, since similar conditions are used for both species. The effect of varying the sperm concentration on fertilization of cumulus-free or cumulus-intact mouse ova was studied.
The results were as follows:
1. Egg retrieval following superovulation. in mice was 14.96.36 eggs ovulated per mouse.
2. Of total eggs retrieved, only 56. 1% of eggs snowed good quality which has no evidence of fragmentation of the cytoplasm or globules of unequal size.
3. In comparison with three grouped sperm concentration and cumulus-free or cumulus-intact ova_ after 96 hours in vitro culture, cleavage rate were 11. 938.47% at low sperm concentration (1 x 105/ml) by cumulus-free ova. 14.47=9.09% at low sperm concentration by cumulus-intact ova, 21.7--4-9.57A0 at medium sperm concentration(lx 106/ml) by cumuls-free ova, 20.399.6000 at medium sperm concentration by cumulus-intact ova, 9,7:j:8.62% at high sperm concentration (I x 107/ml) by cumulus-intact ova, and 10.04-7.17% at high sperm concentration by´cumulus-free ova.
4. A maximum morula or blastocyst formation rate was about 21% which was obtained at the concentration of ´1 x 106 sperm/ml.
5. At low sperm concentration or higher one morula or blastcyst formation declined, significantly.
6. Morula or blastocyst formation rate was significantly improved, when cumulus intact ´ oocytes were inseminated with sperm at low sperm concentration relative to cumulus-free oocytes.
7. There was no significant difference of cleavage rate between cumulus-free and cumulus-intact ova using high and medium sperm concentration.
Optimal sperm concentration in vitro fertilization of mouse oocyte was considered as 1,/ 105/ml to l x 10´ /ml and the most optimal concentration was considered as 1 x 106/ml.
Mouse oocytes that have been stripped with hyaluronidase have shown no adverse effect on fertilization and subsequent embryo cleavage using a optima´: sperm concentration.
Therefore, in human oocytes with unsure grading by virture of morphologic characteristics of oocyte cumulus-complex, the use of hyaluronidase is a reliable system in determining precise maturation and in insemination´s being performed in the individual oocytes. Acordingiy, it is regarded as possible to raise fertilization or cleavage rate i human in vitro fertilization program.
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