You can find a good overview of commands and interpretation of meta-analysis in Stata here:

http://www.biostat.jhsph.edu/~fdominic/teaching/bio656/software/meta.analysis.pdf

Regards

Thanks Alexander.

I just get the Exp(B) from the b-coefficient.

Then I run meta command in stata.

Worked perfectly.

So, regression b-coefficients can also be used as Effect size in Meta-analysis.

Regards,

Raul

This comment also helped.

https://stats.stackexchange.com/questions/263655/how-to-perform-a-meta-analysis-of-regression-coefficients

Thanks Sathish