The Effects Of Xylene And Formaldhyde On Mice’s Vitro Fertilization And Embryo Development In Incubator

Objectives In this study, the mices were taken as the research object, the oocytes and sperms were taken as the experimental materials. This study will show us the effects of the different concentrations of xylene and formaldehyde on in vitro fertilization and embryo development and provide experimental datas for controlling the concentration of volatile organic compounds in human assisted reproductive technology laboratory.Methods The concentration of xylene or formaldehyde in the incubator which with the temperature of 37 ℃, 6% CO2 and saturated humidity will be dispatched to 0, 0.3, 1.5, 3.0,15mg/m3 and 0, 0.1, 0.5, 1.0, 5.0 mg/m3, a total of 10 concentration points. We choose the female and male mice which at the age of 10 to 12 weeks and weight of 20 to 25 g as research objects. At each concentration point of xylene or formaldehyde, we assign 10 female mices and 5 male mices randomly,and take out the oocyte and sperm,then put them in the incubator to in vitro fertilization and embryo culture. During this period,we count the fertilization rate, cleavage rate, blastocyst formation rate, blastocyst hatched rate,and use the Laser Scanning Confocal Microscope to observe the change of spindle.Results In the xylene group, the fertilization rate, cleavage rate, blastocyst formation rate and blastocyst hatching rate are different at different concentration point of xylene(P<0.05, the difference has statistical significance. With the increase of the concentration of xylene, the fertilization rate, cleavage rate, blastocyst formation rate and blastocyst hatching rate decrease gradually, there is a dose-response relationship between the concentration of xylene and the fertilization rate, cleavage rate, blastocyst formation rate or blastocyst hatching rate. Under the inverted microscope we can see that, the degeneration and death of embryos is obviously increase with the increase of the concentration of xylene.When the concentration of xylene reach 1.5 mg/m3 or more, the spindles appear some changes like crack or defect. In the formaldehyde group, the fertilization rate, cleavage rate,blastocyst formation rate and blastocyst hatching rate are different at different concentration point of formaldehyde( P<0.05, the difference has statistical significance.With the increase of the concentration of formaldehyde, the fertilization rate, cleavage rate,blastocyst formation rate and blastocyst hatching rate decrease gradually, there is a doseresponse relationship between the concentration of formaldehyde and the fertilization rate,cleavage rate, blastocyst formation rate or blastocyst hatching rate. Under the inverted microscope we can see that, the degeneration and death of embryos is obviously increase with the increase of the concentration of formaldehyde. When the concentration of formaldehyde reach 1.0 mg/m3 or more, the spindles appear some changes like crack or defect.Conclusions 1 With the increase of the concentration of xylene of the incubator, the fertilization rate, cleavage rate, blastocyst formation rate and blastocyst hatching rate decrease gradually, there is a dose-response relationship between the concentration of xylene and the fertilization rate, cleavage rate, blastocyst formation rate or blastocyst hatching rate. When the concentration of xylene reach 1.5 mg/m3 or more, the spindles appear some changes like crack or defect.2 With the increase of the concentration of formaldehyde of the incubator, the fertilization rate, cleavage rate, blastocyst formation rate and blastocyst hatching rate decrease gradually, there is a dose-response relationship between the concentration of xylene and the fertilization rate, cleavage rate, blastocyst formation rate or blastocyst hatching rate. When the concentration of formaldehyde reach 1.0 mg/m3 or more, the spindles appear some changes like crack or defect.3 Xylene, formaldehyde or other VOCs in the incubator have bad effects on in vitro fertilization and embryo development, so we should monitor the concentration of VOCs in the laboratory at any time.