Objective  To examine the effect of knowledge about folic acid supplementation on folic acid intake among childbearing women and to provide evidences for improving interventions on folic acid supplementation by relevant agencies.

  Methods  We recruited 1 495 women with fertility or pregnancy history within previous three years using population proportion sampling in 10 prefectures and Yangling Demonstration Zone of Shaanxi province; then we conducted a face-to-face questionnaire survey on knowledge about folic acid supplementation and folic acid intake during peripartum in July and August, 2016. The prevalence ratio (PR) of folic acid intake in relation to the cognition on folic acid supplementation and its 95% confidence interval (95% CI) were estimated using log-binomial model analysis.

  Results  For the 1 495 participants averagely aged 29.27 years, the reported folic acid intake rate during peripartum was 84.10% and the reported awareness rate of folic acid supplementation during perinatal period was 86.49%, with the knowledge rate of 57.11% and 71.34% for the effect of folic acid supplementation on neural tube defects (NTDs) prevention and for the policy of folic acid supplied by relevant agencies free of charge. A positive correlation between the awareness of folic acid supplementation and folic acid intake remained significant with the induction of covariates. After adjusting for potential confounders, the PR for folic acid intake in relation to cognition on folic acid supplementation during peripartum was 2.97 (95% confidence interval 95% CI: 2.33 – 3.93) and that in relation to awareness of prevention effect of folic acid intake on NTDs prevention was 1.05 (95% CI: 1.01 – 1.10). Sensitive analysis revealed that the awareness of folic acid supplementation during perinatal period and the preventive effect of folic acid on NTDs exerted a significant impact on folic acid intake among various childbearing women (both P < 0.05).

  Conclusion  The cognition on folic acid supplementation is a independent influencing factor for folic acid intake and the awareness on the folic acid supplementation during perinatal period and on the preventive effect of folic acid on NTDs have significant impact on folic acid intake among childbearing women.