Advancing Age May Decrease Mitochondrial Activity in Cumulus Cells

The goal of this study was to compare mitochondrial activity in cumulus cells (CCs) between young and advancing-aged women, the factors that affect mitochondrial activity, and their association with blastocyst quality. This prospective study included 80 infertile women who underwent ICSI between May and October 2023. Participants were divided into two groups: older and younger than 38. The oocyte mitochondrial activity from CCs was evaluated using MitoTracker, and the mean fluorescence intensity (MFI) was also evaluated. The univariate and multivariate analyses revealed a significant difference in the MFI between the woman ≥ 38 age group and the lower age group (162.68 ± 79.87 vs. 228.39 ± 121.38; -value = 0.005; 95%CI 19.97, 111.45). The factors that affected the MFI were women ≥ 38 years of age ( -value = 0.005; 95%CI -111.45, -19.91), total gonadotropin dosages ( -value = 0.006; 95%CI -0.08, 0.01), and gonadotropin-releasing hormone agonist (GnRHa) triggering ( -value = 0.006; 95%CI 36.46, 210.06). However, only women aged ≥38 years remained statistically significant after a multivariable regression analysis ( -value = 0.014; 95%CI -121.00, -14.30). In addition, only male age (mean age ± SD = 38.26 ± 5.13) was associated with high blastocyst quality in univariate and mixed multivariate analyses (OR 0.91; 95%CI 0.56, 3.04). The chemical pregnancy rate was not significantly different between the two age groups (34.5% vs. 56.7%; -value = 0.162; 95%CI 0.2, 1.30). Advancing age decreased mitochondrial activity in CCs but did not affect blastocyst quality. By contrast, male age may be a predictor of high-grade blastocyst quality.