Prenatal vitamins

Ok so I'm in my second trimester now but when I was in my earlier stages of pregnancy still I was taking "One a Day prenatals" but they were making me really nauseous so my dr prescribed me vitafol one ... I'm concerned bc when I read both bottles together the one I was taking has 800mg folic acid and the one my dr prescribed on has 1 mg, how does this even make sense and what should I do? Why would he prescribe me prenatals with such low folic when the daily recommended intake is like 400mg... ?