P-186 ART outcomes in ICSI cycles with normal and morphologically variant (MV) oocytes in the same cohort

Abstract

Abstract Study question To evaluate ART outcomes of ICSI cycles from normal oocytes (A) Vs normal and MV oocytes (B) and all MV oocytes in the cohort (C). Summary answer Clinical pregnancy rate (CPR), Implantation rate (IR) and live birth rates (LBR) were clinically satisfactory even in group C What is known already In routine IVF laboratories, oocytes are subjected to a rapid evaluation using an inverted microscope to evaluate morphological variants in the cytoplasm, peri-vitelline space and zona pellucida, which is very superficial and subjective. Post ICSI, focus entirely shifts to embryo morphology studies and outcome of such morphologically variant oocytes are less explored. Transferring embryos selected by morphological assessment alone and by neglecting oocyte quality may result in compromised in vitro development, low pregnancy rates, miscarriage rates and further negative consequences Study design, size, duration A prospective observational study of 212 women who underwent ICSI cycles from September 2020 to December 2021 were taken up for the study of which, 106 subjects had all normal oocytes in the cohort (A), 67 subjects had both normal and abnormal oocytes (B) and 28 subjects had all morphologically variant oocytes (C) Participants/materials, setting, methods 212 consecutive women aged 24-38 undergoing ICSI cycles in a private fertility hospital were included. ICSI was performed for all oocytes, embryos cultured until Day 5. Primary outcome measure was to compare ART outcomes between three groups. Secondary outcome measure was to determine minimum threshold of normal oocytes required for higher live birth rate by comparing ART outcomes of patients with at least 7 normal oocytes (n = 51) Vs those with <7 normal oocytes (n = 55). Main results and the role of chance The study showed a highly significant difference in CPR (P < 0.0001), IR (P = 0.0001) and LBR (P = 0.01) when embryos with all morphologically normal oocytes were transferred compared to embryos with morphologically variant oocytes were transferred. There was no difference in ICSI outcomes including fertilization rate, ICSI degeneration rate, early embryo development rate and blastulation rate between the three groups. The study also revealed that a minimum of 7 normal oocytes in the cohort gave significant difference in CPR (P = 0.01), IR (P = 0.02) and LBR (P = 0.0005) when compared to the women who had less than 7 normal oocytes in the same cohort. The outcome of each of the normal and MV oocytes were evaluated by culturing the MV oocytes separately in culture until Day 5. The embryos formed from MV oocytes were vitrified separately and was transferred only when there were no embryos were available for transfer from the normal oocytes obtained from the same cohort. Limitations, reasons for caution The study is to be continued further, until >1000 oocytes are evaluated to confirm if more robust results are obtained, so that sample size in all the three groups are also higher. Wider implications of the findings This study implies that instead of discarding or not injecting oocytes with morphological variants, transferring those embryos with some morphologically variant oocytes also results in a clinically satisfactory outcome and live birth rates. Trial registration number Not applicable