P-399 Oocyte vitrification does not impair clinical outcomes in women of advanced maternal age. An analysis of 1268 cycles using fresh and vitrified oocytes

Abstract Study question Does oocyte vitrification impair clinical outcomes in women of advanced maternal age (AMA, >35 years old)? Summary answer Up to the 39 years, were comparable amongst cycles using fresh and vitrified oocytes. What is known already Primarily recommended for young women, most efficient method elective fertility preservation. Nevertheless, various social economic circumstances often compel undergo preservation when at an AMA. Recent studies mouse suggest that AMA increases vulnerability oocytes molecular subcellular damage during vitrification, ultimately compromising embryo viability implantation potential. However, effects on human preimplantation development currently remain unknown. design, size, duration This a retrospective cohort single-center study. We compared 1268 patients undergoing their first ICSI cycle autologous (n = 1087) or 181), performed between January 2019 October 2022. All obtained following age-related decline. Outcomes stratified according pick-up: control group (≤35) groups (36-37, 38-39 ≥40 years). Participants/materials, setting, methods across matching groups. These included fertilization rates, proportion viable embryos day 3, pregnancy live birth rates. Univariate multivariate analyses (2-contrast linear logistic regression) used establish correlations. Analyses adjusting sperm origin (partner donor), transfer (3 5), number transferred endometrial age. p values <0.05 considered significant. Main results role chance Sperm donation homologous equally distributed among study (45% donor 55% male partner entire cohort). In our cohort, blastocyst was less frequently older 23.8% 45.6% ≤35 (p < 0.0001). When comparing status groups, rates ∼10% lower 0.05). Our adjusted analysis confirmed this negative impact Oocyte also affected ongoing cleavage, as 3 significantly all effect did not translate which regardless status. As expected, rate decreased steadily with advancing (from 38.5% 15.0% ≥40). While showed (OR: 0.60, 95%CI: 0.18-2.06), we observed no such ≤39 years. Limitations, reasons caution The main limitation its design. low presentation 39) warrants careful interpretation. cannot be generalized patient populations indications Wider implications findings Clinical up before 35 old remains established effective preventing decline, offer valuable resource counselling considering Trial registration Not applicable