AUTHOR=Yang Liping , Wang Wenjuan , Mao Baohong , Qiu Jie , Guo Huaqi , Yi Bin , He Xiaochun , Lin Xiaojuan , Lv Ling , Xu Xiaoying , Liu Qing , Cao Yongchun , Chen Yiming TITLE=Maternal Folic Acid Supplementation, Dietary Folate Intake, and Low Birth Weight: A Birth Cohort Study JOURNAL=Frontiers in Public Health VOLUME=Volume 10 - 2022 YEAR=2022 URL=https://www.frontiersin.org/journals/public-health/articles/10.3389/fpubh.2022.844150 DOI=10.3389/fpubh.2022.844150 ISSN=2296-2565 ABSTRACT=Objectives: To investigate the independent and collective effects of maternal folic acid supplementation or dietary folate intake upon the risk of low birth weight (LBW), and to further comprehensively examine the joint associations of folic acid supplementation and dietary folate intake with LBW by various clinical subtypes. Design: Participants were recruited in Gansu Provincial Maternity and Child Care Hospital. A standardized and structured questionnaire was distributed to collect demographic factors, reproductive and medical history, occupational and residential history, physical activity and diet. Data on pregnancy-related complications and birth outcomes were extracted from medical records. Unconditional logistic regression models were used to estimate odds ratio (OR) and 95% confidence interval (95%CI) for single and joint associations of folic acid supplementation and dietary folate intake with LBW. Setting: A birth cohort data analysis using the 2010–2012 Gansu Provincial Maternity and Child Care Hospital in Lanzhou, China. Participants: 9231 pregnant women and their children were enrolled in the study. Results: Compared to non-users, folic acid supplementation was associated with a reduced risk of LBW (OR: 0.80, 95%CI: 0.66-0.97), and the reduced risk was mainly seen for term-LBW (OR: 0.59, 95%CI: 0.41-0.85), and multiparous-LBW (OR: 0.72, 95%CI: 0.54-0.94). For dietary folate intake, there were no significant associations with LBW, and there was no interaction of folic acid supplement and dietary folate intake on LBW. Conclusions: Our study results indicated that folic acid supplementation was associated with a reduced risk of LBW, and there was not interaction of folic acid supplement and dietary folate intake on LBW.