Let g be a finite dimensional real Lie bialgebra.We introduce an R -valued cohomology of g for which the space of all inequivalent Lie bialgebra central extensions of g by R is isomorphic to that second cohomology group of g .Furthermore, we study the natural projection of this group on the R -valued Lie algebra second cohomology group of g .
M. Benayed (Wed,) studied this question.