Spermidine promotes fertility in aged female mice

Female fecundity decreases one to two decades before the menopausal transition. A study by Zhang et al. now identifies aging-related decline of the polyamine spermidine as a crucial bottleneck for oocyte quality. Supplementation with spermidine rejuvenates oocytes in vitro and in vivo, and leads to improved fertility of middle-aged female mice.