I don't think it's mandatory but highly recommended
i dont take prenatal. i take flinstones. prenatals make me sick..
my cousin never took then for her last to pregnancy and her boys were 9lbs and 11lbs ....but I wouldn't know I know all my doc Appt they make sure to tell me I need to take some kind of vitamins
I freak out of I miss a dose lol healthy for baby and mama.. I would never stop taking them just keep trying new ones until u find what works