Fig. 1
From: Prevalence and determinants of preconception folic acid use: an Italian multicenter survey
The prevalence of folic acid supplement users according to time periods of use (n = 2,189). Time periods of use were defined as at least one month before the last menstrual period to the end of the first trimester, at least six months before the last menstrual period to the end of the first trimester, soon after pregnancy confirmation to the end of the first trimester, after the first trimester of pregnancy, or no use at all