Aim: To evaluate whether embryo selection using the early embryo viability assessment (EEVA) score increases the ongoing pregnancy rate of in vitro fertilization and intracytoplasmic sperm injection patients.
Methods: One hundred eighty-one patients whose serum anti mullerian hormone (AMH) level was greater than 0.5 ng/μL were enrolled in the study. All patients received oocyte retrieval repeatedly from June 2017 to January 2019. Transferred embryos were selected using the EEVA score and Veeck's criteria. We investigated the blastocyst rate according to the EEVA score and Veeck's criteria and also evaluated the clinical outcome following embryo transfer of the blastocysts.
Results: Blastocyst development rate (48.7%) and high-quality blastocyst (42.4%) of Veeck 1 was statistically higher than others. The blastocyst rate (71.4%) and high-quality blastocyst rate (60.0%) for EEVA 1 was the highest, and a correlation between the EEVA score and the blastocyst rate was also identified in cases younger than 40 years. Blastocyst rate of EEVA 1 + 2 (69.8% 208/298) was statistically higher than that of Veeck 1 + 2 (40.1% 317/791) (p < 0.05) and high-quality blastocyst rate of EEVA 1 + 2 (50.0% 104/208) was also higher than that of Veeck 1 + 2 (36.6% 117/320) (p < 0.05). However, there was a significant correlation between EEVA and the pregnancy rate and pregnancy rate of EEVA 1 + 2 showed no statistical difference compared with Veeck 1 + 2.
Conclusions: Although it remains to be answered whether a computer can substitute Veeck's classification, the EEVA score could be a viable alternative to predict the blastocyst rate and to select those high-potential embryos that improve the pregnancy rate.
Keywords: EEVA score; ICSI; IVF-embryo transfer; blastocyst rate; time-lapse instrumentation.
© 2021 Japan Society of Obstetrics and Gynecology.