A review of the latest measurements of the primordial abundances of the light nuclei D , ^ { 3 } He , ^ { 4 } He and ^ { 7 } Li is given .
We discuss in particular the primordial abundance Y _ { p } of ^ { 4 } He as measured in blue compact dwarf galaxies .
We argue that the best measurements now give a “ high ” value of Y _ { p } along with a “ low ” value of D/H , and that the two independent measurements are consistent within the framework of standard Big Bang nucleosynthesis with a number of light neutrino species N _ { \nu } = 3.0 \pm 0.3 ( 2 \sigma ) .