Age or Ovarian Reserve? A Comparative Study of IVF Outcomes in Young Women with DOR and Older Women with NOR

Abstract

The aim of this study was to evaluate whether chronological age or ovarian reserve exerts a greater influence on in vitro fertilization (IVF) outcomes. A retrospective cohort analysis was conducted, including 108 women undergoing IVF at In vitro OG Medical Centre Dimitrov between 2018 and 2024. Participants were classified as OLDER NOR (age > 35 years, AMH ≥ 1.5 ng/ml) and YOUNG DOR (age ≤ 35 years, AMH ≤1.1 ng/ml). Although women in the OLDER NOR cohort exhibited higher AMH levels, younger women with diminished ovarian reserve achieved better clinical outcomes – higher fertilization, clinical pregnancy, and live birth rates. These findings suggest that chronological age has a stronger impact on embryo competence and implantation potential than ovarian reserve markers alone, highlighting the predominant role of age in determining reproductive success in IVF cycles.