The present invention relates to the use of a cyclic peptide comprising the tripeptide reproducing a binding site of fertilin beta to the oocyte integrin, for improving cellular energy metabolism. More particularly, the invention concerns the use of a cyclic peptide comprising the tripeptide FEEc for stimulating the energy metabolism of gametes or embryonic cells in the context of medically assisted procreation (MAP) protocols, in particular promoting the in vitro maturation of the oocyte, the fertilization rate and the birth rate.
