“…Previous studies have quantified the use of vitamins and minerals in pregnancy 1,4,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38 , and some have addressed its association with age 11,12,13,30,31,38 , ethnicity 8,12,13,30,33 , education 11,13,18,30,31,36,38 , marital status …”