RÉSUMÉ
This study was carried out to determine the effect of the duration of exposure to the infrared 1.48 mm diode laser, on the developmental potential of cleavage stage embryos. A total of 69 mouse embryos were included in the study. Twenty-two of which (group A) were biopsied using the laser with a longer duration of exposure (600 ms), meanwhile 47 (group B) were biopsied using the same laser with a shorter period (5 ms). The blastocyst formation rate of group B (46/47, 97.8%) was significantly higher than that of group A (12/22, 54.4%). There were no grade 1 blastocysts or hatching in group A. In contrast, 35 of 46 (76.0%) blastocysts in group B were grade 1 and the hatching rate of group B was 84.7% (39/46). In conclusion, the infrared 1.48 mm diode laser may be effective and safe with cautious application. A long duration of exposure to the laser can adversely affect the developmental potential of the biopsied embryos. The laser system with a shorter duration of exposure, therefore, is recommended for laser assisted embryo biopsy.