P-728 Age limits in medically assisted reproduction: Assessing clinical and pregnancy outcomes in women over 50 years of age undergoing donor oocyte in vitro fertilization

Abstract

Abstract Study question Is pregnancy in women over 50 years of age undergoing donor oocyte IVF associated with adverse clinical and pregnancy outcomes? Summary answer In vitro fertilization treatment in women over 50 years of age using donor oocytes is not associated with adverse clinical and pregnancy outcomes. What is known already In vitro fertilization with donor oocytes (d-IVF) has become a common strategy for managing cases of very advanced maternal age. However, there is ongoing scientific debate entailing legal and societal implications regarding the age limit beyond which d-IVF should no longer be considered safe. Different age limits and guidelines have been proposed, with no globally accepted consensus. The most commonly reported age limit is 50 years, representing the median age of menopause. However, there is a lack of robust data to support that d-IVF beyond the age of 50 is associated with adverse clinical and pregnancy outcomes. Study design, size, duration A retrospective single-centre study was conducted to evaluate medical records of d-IVF cycles between July 2021-January 2023. A total of 575 medical records of women undergoing d-IVF were analyzed. The study population was divided into two groups based on maternal age: women aged 45-49 years (group A, n = 318) and women aged 50-54 years (group B, n = 257). The outcome measures were positive-hCG, clinical pregnancy, viable pregnancy at 12 weeks of gestation, pregnancy loss and live birth. Participants/materials, setting, methods For oocyte recipients advanced maternal age was the sole infertility etiology and endometrial preparation was performed employing conventional protocols. Oocyte donors were up to 35 years of age and oocyte donation cycles were performed according to national guidelines. Single or double embryo transfers (ETs) were performed at the cleavage or blastocyst stage. Embryo quality assessment was performed according to Veeck and Gardner grading systems. Statistical analysis was performed employing R Programming Language for Statistical Purposes. Main results and the role of chance The mean age of group A was 47.02 ± 1.35 while the mean age of group B was 51.84 ± 1.59. No statistically significant difference was observed regarding the age of oocyte donors (25.17 ± 4.18 vs 26.09 ± 4.13; p-value=0.26). Considering embryo transfer, 90 cleavage stage and 228 blastocyst stage transfers were performed in group A, and 75 cleavage stage and 182 blastocyst stage transfers were performed in group B (p-value=0.23). No statistically significant difference was observed between the two groups with regards to the number of transferred embryos (1.89 ± 0.35 vs 1.90 ± 0.36; p-value=0.69) and embryo quality (Group A: Good 157, Fair 143, Poor: 18; Group B: Good 121, Fair 117; Poor 19; p-value=0.66). Considering clinical and pregnancy outcomes no statistically significant difference was observed between the two groups regarding positive hCG rate (147/318 vs 109/257, respectively; RR: 0.91; 95%CI: 0.76-1.10; p-value=0.36), clinical pregnancy rate (129/318 vs 98/257, respectively; RR: 0.94; 95%CI: 0.77-1.15; p-value=0.55), viable pregnancy rate at 12 weeks of gestation (96/318 vs 70/257, respectively; RR: 0.90; 95%CI: 0.70-1.17; p-value=0.44), pregnancy loss rate (39/129 vs 33/98, respectively; RR: 1.13; 95%CI: 0.76-1.63; p-value=0.58) and live-birth rate (90/318 vs 65/257, respectively; RR: 0.91; 95%CI: 0.68-1.17; p-value=0.42). Limitations, reasons for caution The retrospective and the single-centre nature of the study are important reasons for caution. In addition, the relatively small sample size may serve as another limitation. The lack of neonatal outcomes may also be considered an additional limitation when interpreting data on the safety of d-IVF in the over-50s. Wider implications of the findings Women over 50 who undergo d-IVF are not at increased risk of complications. This highlights the need to reconsider age limits and provide robust evidence ascertaining both safety and reproductive autonomy. Studies are needed to assess neonatal outcomes and maternal age impact on long-term infant health from an epigenetic standpoint. Trial registration number Not applicable