PIK3CD and Infertility: Given the similarity in phenotypes of retarded oocyte growth and infertility in mice between constitutive expression of Foxo3a in oocytes and present Rps26fl/fl/Gdf9-Cre mice, we hypothesized that disruption of PI3K/Akt/Foxo3a pathway might be responsible for the failure of oocyte maturation and infertility of Rps26fl/fl/Gdf9-Cre females.