But because some people do not plan their pregnancies, several countries require that the grains used to make bread, breakfast cereals and suchlike be fortified with folic acid.

• 不过，由于有些人生孩子之前没有计划，个别国家规定：凡是谷物，不论用于制作面包、早餐麦片或其他食物，都要添加叶酸。