Objective: We conducted a systematic review of studies designed to increase awareness of knowledge about, and consumption of folic acid before and during pregnancy.
Data sources: Studies were identified from Cochrane Library, Medline, and the references of primary studies and reviews.
Study inclusion and exclusion criteria: Studies included randomized controlled trials, quasi-experimental interrupted time series studies, follow-up studies, case-control studies, and before-and-after studies, all of which were conducted between 1992 and 2005 on women ages 15 to 49 years and/or health professionals, evaluating awareness and/or knowledge and/or consumption of folic acid both before and after intervention. Studies were excluded if data were not presented both before and after intervention or were other outcomes than those mentioned here.
Data extraction: Data were extracted in relation to characteristics of studies, participants, interventions, and outcomes.
Data synthesis: Because of heterogeneity, we performed a narrative synthesis describing the direction and the size of effects.
Results: On average, women's awareness increased from 60% to 72%, knowledge from 21% to 45%, and consumption from 14% to 23%.
Conclusions: Interventions had a positive effect on folic acid intakes before and during pregnancy, although the average usage reached less than 25%.