Mitochondrial staining and membrane potential in Control, OTO-Cold, and OTO-Warm oocytes. (A) Mitochondrial staining of a mature oocyte. In the upper panel, mitochondria with high membrane potential emit in red fluorescence. In the middle panel, mitochondria with compromised membrane potential emit in green fluorescence. In the lower panel, is a merged image from red and green channels. (B) Box plot representing the intensity of red/green fluorescence in Control, OTO-Cold, and OTO-Warm oocytes. OTO-COLD, in vitro matured ovarian tissue oocytes from transgender men collected from ovaries transferred in cold medium; OTO-WARM, in vitro matured ovarian tissue oocytes from transgender men collected from ovaries transferred in prewarmed medium.