Nicotinamide (NAM) is an important antioxidant, which is closely related to female fertility, but its role has not been clearly elucidated. The purpose of the present study was to investigate the effects of NAM on follicular development at different stages and the quality of oocytes...Higher levels of NAM in FF are associated with larger follicle development. The supplement of 5 mM NAM during IVM may improve mice oocyte quality, reducing damage caused by oxidative stress.