Affect of low intensity light on mice embryo development using the time laps “EmbryoGuard” system

Abstract

Objective: The objective of this study was to asses the affect of exposure time of low intensity white LED (light emitting diode) light on mice embryos using the time laps “EmbryoGuard” system. Design: 2PN embryos were divided into two groups: short light exposure compared to long white LED light exposure (400–700 nm). The embryos in the long exposure group were exposed to the light source continuously until reaching the blastocyst stage. Materials and Methods: 2PN stage embryos were flushed from CB6F1 female mice. The embryos were divided into 20μl, M16 (Sigma, St. louise, USA) drops, each drop containing 25 embryos, and cultured under mineral oil (Sigma, St. louise, USA). The long exposure group was placed in the incubator at 37°C, 5% CO2 and 95% humidity under a white (400–700 nm) LED light source (Nichaia Corporation, Japan) until reaching the blastocyst stage. The short exposure group was divided in the same manner and placed in the same incubator unexposed to light. Embryonic development was determined by the number of embryos that reached the 2 cell stage and subsequently the blastocyts stage. The groups were compared initially using Chi-square (χ2) analysis. If significant differences existed among groups, pair wise comparisons were made. Probabilities of treatment difference p < 0.05 were considered significant. Results: Embryonic development: Tabled 1 Embryonic development in the long exposure group did not differ significantly (p < 0.05) from the short exposure group cleavage rate and its subsequent development into blastocysts. Conclusions: Intensity of light used in a microscope is in average 5300 candelas, the white LED light used in the EmbryoGuard system is only 9.2 candelas. Despite the fact that the embryos were exposed continuously to the white LED light, embryonic development was not affected. We conclude that the illumination did not affect the embryo’s growth. pain and pain before the OPU. During the OPU the EA group had significantly higher VAS scores, consistent with the nurses’ VAS-rating compared with the CMA group. There were no significant differences between the groups regarding pain after the OPU at the clinic, and no significant differences in the patients’ home rating. The use of supplementary painkillers did not differ in the groups. Preparation and procedure time did not differ in the two groups. Patients in the EA group were discharged significantly quicker and “medication” costs were significantly lower in the EA group. 87% of the patients who had EA would prefer EA again as an anaesthetic method for OPU. The clinical outcome parameters did not differ among groups showing high pregnancy rates per embryo transfer in both groups Conclusion: A significant difference was found between the EA and the CMA groups regarding VAS pain scoring during the OPU, but not before or after the procedure. Nevertheless 87% of patients would prefer EA again for OPU. Generally patients were very positive to EA feeling less confused and more present during the OPU, and without tiredness and drowsiness for the rest of the day. Costs and time to discharge were lower for the EA group. EA is a good alternative to conventional anaesthetics during OPU, with a high patient compliance.