preggo multivatamins

may vitamins are obimin plus and calvit and anmum..preo since nung pinagtake aq ng calvit super constipated na aq..cnabi q un sa ob q en sabi nya stop q nlng daw..pwede na ung milk 2x a day..in short wala na po aq multivitamins other than my anmum..cno po sa inyo ganito..d kya kulangin ng vitamins c baby