Age-Related Dynamics in Endometrial Vascularity: A Comprehensive Three-Dimensional Ultrasound Evaluation During Follicular and Luteal Phases

Abstract

Objective: Transvaginal ultrasonography plays a crucial role in contemporary fertility management, offering insights into uterine and endometrial blood flow. Three-dimensional ultrasonography utilizing power Doppler angiography (3D-CPA) allows precise measurement of endometrial volume and vascular parameters, such as the vascularization index (VI), blood flow index (FI), and vascularization flow index (VFI); variables that indirectly assess endometrial receptivity and integrity. Doppler technology allows for the capture of changes in the uterus induced by hormonal-related fluctuations during the menstrual cycle, revealing a significant correlation between endometrial receptivity and vascularity. Age-related changes in endometrial function are implicated in declining fertility, with limited research exploring this aspect. The aim of this study was to investigate the impact of aging on various ultrasound parameters of the uterus, including endometrial vascularity. Methods: A retrospective cross-sectional study of women who attended the Feto-Maternal Centre from January 2022 to December 2023. Each woman whose menstrual cycle was regular underwent 3D ultrasound with power Doppler as part of the routine assessment of the pelvis. Parameters assessed include the VI, FI, and VFI as well as uterine volume, endometrial volume, and endometrial thickness. The women were grouped based on age, and the variables measured in the follicular and luteal phases were compared between the age groups using SPSS version 30 September 2024. Results: A total of 907 women (427 follicular and 480 luteal phase) were studied: 297 (131 follicular and 166 luteal) were 20–29 years old; 471 (240 follicular and 231 luteal) were aged 30–39; and 139 (56 follicular and 83 luteal) were aged 40–49. Uterine volume, endometrial volume, and thickness increased significantly and steadily with age. VI, VFI, and FI decreased significantly with age in the follicular phase, but in the luteal phase there was no statistically significant difference in any of these indices with age. Conclusions: Uterine volume, endometrial thickness, and endometrial volume increased with age, but the vascular indices decreased with age in the follicular but not in the luteal phase. These age-related changes in endometrial vascularity may partly explain the decrease in age-related fertility. Further research is needed to comprehensively explore the complexities of uterine aging and its implications for female fertility.