@ARTICLE{, author = {}, title = {Effects of Overcrowding on Mice Blastocyst}, volume = {18}, number = {3}, abstract ={Introduction: The increase of social stress following the technological improvements appears to be an important factor that causes psychosomatic disorders and finally results in infertility. Since anxiety and depression are more prevalent in women than men, it seems the effect of stress can be observed more in female organs such as genital system. Therefore, the present study was conducted to investigate the effect, of stress on number and quality of flushed mice blastocysts. Materials & Methods: In our study, 50 mature female mice of the Swiss Albino species were selected and randomly divided into 3 groups. Group 1 as control group(low stress group) with 5 mice in a cage (3 cages), Group 2 (high stress group) with 10 mice in a cage (2 cages), and Group 3 (high stress group) with 15 mice in a cage (1 cage). Each group was kept in a special mouse cage for one month. After 1 month, the animals were induced to superovulate with i.p injections of 10 IU of PMSG and 10 IU of HCG given 48 h apart, and were mated with Swiss Albino male mice. Mice with positive vaginal plug were placed again as 5, 10 and 15 members in their cages. After 98 h post HCG injection, embryos, mostly at the blastocyst stage, were collected from the uteri of mated animals by flushing. The number of flushed blastocysts, and blastomers in each embryo in 3 groups were analyzed statistically. Findings: Our results showed that the mean number of flushed blastocysts in control low stress group (7.7±2.8) and high stress group (2.4±2.1) was significantly lower than control group (14.8± 3.4), and also the mean number of blastomers in low stress group and high stress group showed no significant difference in comparison to control group. (P=0.176) Discussion & Conclusion: It can be concluded that overcrowding could be considered an important factor in infertility by decreasing the number of flushed blastocysts in mice. }, URL = {http://sjimu.medilam.ac.ir/article-1-231-en.html}, eprint = {http://sjimu.medilam.ac.ir/article-1-231-en.pdf}, journal = {Journal of Ilam University of Medical Sciences}, doi = {}, year = {2010} }