Fig. 2.

MtDNA copy number for CCs (n = 60) and PBCs (n = 18) and the association with embryo quality. Median mtDNA contents of CCs of good- and bad-quality embryos were 140 (25–75 % quartile, 97–264) and 57 (25–75 % quartile, 34–74), respectively. The median mtDNA contents of PBCs for good- and bad-quality embryos were 36 (25–75 % quartile, 18–46) and 13 (25–75 % quartile, 11–44), respectively. The p value was calculated using the Mann-Whitney U test. mtDNA mitochondrial DNA, PBCs peripheral blood cells, CCs cumulus cells