What prenatal vitamins?

Eleesha
I went to the chiropractor the other day due to torsion in the hip causing back pain and knotted muscle in the lower back and be brought up prenatal vitamins and told me to be sure to take one with DHA as well as making sure it was certified (I can't remember by whom) to make sure it was quality vitamins. What does everyone suggest and would anyone know what the certified thing he was talking about?