Lower live birth rates with increasing maternal age in donor oocyte cycles

Maternal age has a significant impact on the outcome of in vitro fertilization (IVF). However, it is important to delineate outcomes in relation to the contribution of the oocyte and uterus in relation to age. Although age related oocyte chromosomal factors are clearly detrimental, the role of the uterus in older patients is not as clear [1, 2]. The objective of this study was to evaluate IVF outcomes in patients over the age of 50 undergoing donor oocyte cycles. This was a retrospective cohort study that included all embryo transfer cycles using donor oocytes between 01/2015-12/2021 in patients >40 years of age. Data on BMI, paternal age, type of cycle (natural vs. medicated), number of embryos transferred, was evaluated in relation to miscarriages and live births when comparing age groups of 40-44, 45-49 and >50. The statistical analysis was performed using a logistic regression model. A total of 2,087 embryo transfer cycles using donor oocytes in patients >40 years were performed during the study period, of which 1,207 were in patients 40-44, 749 in patients 45-49 and 131 in patients >50 years of age. The mean number of embryos transferred was 1.21±0.41. The presence of implantation was significantly lower in patients >50 (P=0.011), and the presence of a live birth was significantly lower in patients 45-49 and >50, compared to those 40-44 (P=0.018 and P=0.014, respectively). This relationship persisted after adjusting for BMI, paternal age, type of embryo transfer cycle (natural cycle vs medicated cycle) and type of oocyte donor (fresh vs frozen oocyte donor) (Table 1). While oocyte quality is a major determinant of IVF outcomes, additional factors such as uterine aging must also be considered. Even with the use of donor oocytes, maternal age appears to have an impact on implantation and subsequent live birth.