en 30859076 <p>Background: Artificial oocyte activation (AOA) is a specialized method in assisted reproductive technique (ART). According to increasing concern about using AOA, it is necessary to evaluate sperm-borne oocyte activating factors (SOAFs) including phospholipase C zeta (PLC&zeta;). In this study, PLC&zeta; before AOA was evaluated first and then the impact of AOA on pre-implantation embryo development was investigated.<br /> Methods: This prospective clinical trial enrolled couples subjected to ICSI. By evaluating PLC&zeta;, semen samples were categorized into two groups; I (Control) and II (PLC&zeta; deficient). Retrieved oocytes from partners were put into three categories: control group (Injected with sperm from group I, n=113), group without AOA (Injected with sperm from group II and no exposure to AOA, n=106), and group AOA (Injected with sperm from group II and exposure to AOA, n=114). Finally, fertilization results were compared via Kruskal-Wallis followed by Dunn&rsquo;s multiple comparison test. The p&lt;0.05 was considered statistically significant.<br /> Results: Fertilization rate was significantly lower in the group without AOA compared to control group (41.9&plusmn;6.3 <em>vs.</em> 78.1&plusmn;4.7, p&lt;0.001). AOA improved fertilization rate in group AOA compared to the group without AOA (69.5&plusmn;3.9 <em>vs.</em> 41.9&plusmn;6.3, p&lt;0.01); however, cleavage (91.7&plusmn;2.8, 90.9&plusmn;4.6, and 95.2&plusmn;3.4, respectively) and embryo quality (2.5&plusmn;0.1, 2.3&plusmn;0.2, and 2.4&plusmn;0.2, respectively) scores were not substantially different between groups of control, with and without AOA.<br /> Conclusion: We showed that PLC&zeta; can be considered as a good biomarker in evaluation of oocyte activation capability. Further studies are required to establish the best use of PLC&zeta; as a biomarker in clinics.</p> Artificial oocyte activation, Biomarker, Intra-cytoplasmic sperm injection, Phospholipase C zeta, Sperm 03 10 https://www.jri.ir/article/30046 https://www.jri.ir/documents/fullpaper/en/30046.pdf HamidNazarianDepartment of Biology and Anatomical Sciences, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran31907NahidAzadDepartment of Reproductive Biology, School of Medicine, Semnan University of Medical Sciences, Semnan, Iran31908LeilaNazariDepartment of Obstetrics and Gynecology, Preventative Gynecology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran31909AbbasPiryaeiUrogenital Stem Cell Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran31910Mohammad HassanHeidariDepartment of Biology and Anatomical Sciences, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran31911RezaMasteri FarahaniDepartment of Biology and Anatomical Sciences, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran31912MaryamKarimiInfertility and Reproductive Health Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran31913MarefatGhaffari NovinInfertility and Reproductive Health Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iranmghaffarin@yahoo.com, mghaffarin@sbmu.ac.ir31914