P-254 Short-time or overnight co-incubation with sperm in conventional IVF delivers similar pre-implantation development outcomes: a sibling cumulus-oocyte complex study

Abstract Study question Does a short-time co-incubation in conventional IVF improve rates of fertilization, embryo development and euploidy, when compared to overnight co-incubation? Summary answer There is no significant difference euploidy between sibling oocytes subjected short versus co-incubation. What known already Conventional usually implies coincubation cumulus-oocyte complex(es) with sperm for an period. This incubation might create over exposure COCs reactive oxygen species (ROS), which disturb oocyte homeostasis, impact on embryonic developmental rate. To this extend, many early studies have time (2-6 hours) co-incubation, reported conflicting outcomes. None the combined time-lapse monitoring allows identification morphokinetic events inseminated after IVF, as ICSI incubators. design, size, duration single center prospective study included 604 38 IVF/ICSI cycles preimplantation genetic testing December 2020 November 2022. After retrieval min 6 were assigned insemination by equally divided short(2hrs) (16-20hrs) Supernumerary denuded ICSI. Primary endpoint was fertilization rate; secondary endpoints maturation rate, ploidy rate trophectoderm biopsy, morphokinetics. Participants/materials, setting, methods Couples female age 18-43 (average:34.4) years, BMI ≤30kg/m2 normal semen parameters (WHO) fresh ejaculate day OR, eligible study. all embryos cultured imaging system Global Total LP media. Blastocysts (≥Bl3BCC) biopsy 5-7 next generation sequencing (NGS) determine blastocyst status. Main results role chance In total, 288 (47.7%) ICSI, whereas 316 (52.3%) randomized 1:1 groups. Maturation (M2/COC) (2PN/COC) groups similar (88.0% vs 83.5%, P = 0.074 60.8% 62.0%, 0.193, respectively). Day-3 cell numbers (P 0.383), fragmentation 0.529), blastulation 5 (39.9 38.0% 0.696), (median: 112.6 111.1 hours lapse, 0.544) 48 45 sufficient quality resulting (39.6 44.4%, 0.791). When their siblings (mean difference: -6.48%, 95% CI: -18.5 5.59%, 0.290) -0.87%, -12.9 11.2%, 0.886) attained per cycle. No differences regarding observed or unadjusted adjusted analyses. Limitations, reasons caution limited patient population ovarian response. Results not be transferable patients high low reserve. Wider implications findings The present demonstrated that there terms rates. Therefore allow us benefit from denudation, investigate morphokinetics lapse monitoring, are otherwise missed Trial registration number NCT04627545