Question :

Is it permissible for a praying person to make supplication in each Sajdah( a prostration) of obligatory prayer?

The Answer :

It is permissible for a praying person, whether praying individually, or in congregation, to make supplication during Sujood(prostration) in obligatory, or voluntary prayers. However, it is disliked for the Imam to do so since he is required to spare the prayer performers any sort of hardship, unless he is leading a certain group who don`t mind him extending the prayer.