Effects of installing a volatile organic compound-removal filter in a clinical embryology laboratory on embryo development

Objective: Improving embryo quality is essential for increasing pregnancy and live birth rates in assisted reproductive technology (ART). The culture environment strongly influences embryo quality, and air quality is one of its key components. Volatile organic compounds (VOCs) present in clinical embryology laboratories and incubators have been suggested to adversely affect gametes and embryos. This study examined whether installing a VOC-removal filter in a clinical embryology laboratory affected fertilization rate, cleavage rate, blastocyst formation rate, and good-quality blastocyst rate.Methods: A VOC-removal filter was installed in the clinical embryology laboratory to reduce ambient VOC concentrations. Embryological outcomes before and after filter installation were compared in both in vitro fertilization and intracytoplasmic sperm injection (ICSI) cycles. The evaluated outcomes were fertilization rate, cleavage rate, blastocyst formation rate, and good-quality blastocyst rate.Results: VOC concentrations decreased after filter installation; however, blastocyst formation rates did not differ significantly between the pre-installation and post-installation periods. In analyses restricted to ICSI cycles, the proportion of good-quality blastocysts was significantly higher after filter installation than before installation (p=0.0069).Conclusion: These findings suggest that VOCs in the clinical embryology laboratory may adversely affect embryo quality, particularly in ICSI cycles, which involve relatively prolonged laboratory handling. Management of VOC concentrations may therefore be an important component of efforts to improve embryo culture conditions in ART.