Oocytes with smooth endoplasmic reticulum aggregates do not impact blastocyst euploidy rate

Objective: To investigate whether the euploidy rate of blastocysts derived from smooth endoplasmic reticulum (SERa) positive cycles and oocytes are impacted. Design: Retrospective cohort study. Setting: A tertiary hospital-based reproductive medicine center. Patient(s): A total of 601 preimplantation genetic testing (PGT) cycles with obtained oocytes in our center between April 2017 and May 2021 were included in the study. Intervention(s): Women＞35 years and PGT cycles with chromosomal structural rearrangements (PGT-SR) were excluded. Embryological and blastocyst ploidy outcomes were compared between SERa+ oocyte, sibling SERa- oocytes and oocytes in SERa- cycles. Main Outcome Measure(s): Embryological outcomes and blastocyst euploidy rate. Results: : No significant difference was observed in the normal fertilization rate (82.1 % vs. 77.8 % vs. 83.1 %, respectively, P =0.061), blastocyst formation rate (71.0 % vs. 72.5 % vs. 68.4 %, respectively, P =0.393), good quality blastocyst formation rate (46.4 % vs. 48.3 % vs. 42.6 %, respectively, P =0.198) between the SERa+ oocyte group, sibling SERa- oocyte group and SERa- oocyte group. No significant difference was observed in the euploidy rate (50.0 % vs. 62.5 % vs. 63.3 %, respectively, P =0.324), mosaic rate (12.5 % vs. 9.7 % vs. 13.4 %, respectively, P =0.506) and aneuploidy rate (37.5 % vs. 27.8% vs. 23.2 %, respectively, P =0.137) between the three groups. Conclusion: Our results suggest that the euploidy rate of blastocysts derived from SERa+ cycles and oocytes are not impacted.