Is 13,000 IU Of Vitamin-A Taken Per Day For Fetal Growth Advisable?

Hi Dr. I am 6 months pregnant right now. My OB says that my baby is too small base on my weight and size of my tummy, so she prescribed me to take 13,000 IU of vitamin A per day for two weeks for me and my baby to get into it s normal size. Is that ok? Thank you... Ilet