Background: Extra embryos developed during IVF have led to different freezing methods with variety of antifreezes. The present study was conducted with the aim of determining the effects of ethylene glycol on mouse ova development and existence following the freezing procedure.

Materials and Methods: It was an experimental study. Oocyte was obtained and fertilized by sperm. 16-17 hours later zygotic cells were distributed randomly in three groups of control, toxicity and freezing. In freezing group, embryos were frozen slowly by two antifreezes, ethylene glycol and propandiol, according to the standard procedure. Lived embryos were cultured for 120 hours. Then their development was compared with that of control group.

Results: Toxicity test results have shown no significant difference considering zygotes’ viability and development between the control and freezing groups. Following the procedure, viability of cells in propandiol group was significantly higher than that of ethylene glycol (94.1% vs. 58.2%), meanwhile, the rate of cell development till blastocyte was significantly higher in the propandiol group (68.2% vs. 39.1%, P<0.0001).

Conclusion: Ethylene glycol is not a suitable alternative for propandiol in slow freezing. Results of cell viability and development revealed that propandiol could be an appropriate substance for freezing human zygotes.