RESUMO
OBJECTIVE: To examine the association between folic acid supplements during peri-conception and the related adverse birth outcome. METHODS: Pregnant women who received first prenatal care at 4 municipal-level medical institutions in Maanshan, from Oct. 2008 to Oct. 2010 were selected as the target population. All participants were asked to complete a self-administered questionnaire which including data on demographic characteristics, interval, complications and frequency of taking folic acid etc., during pregnancy. The follow-up-records after delivery would include factors as: fetal weight, height, circumference of head, chest circumference of the neonates. Finally, 4448 valid questionnaires were gathered, including 190 premature, 147 small for gestational age and 104 low birth weight babies. Descriptive statistics and logistic regression models were used for data analysis. RESULTS: Data showed that the weight, height and head circumference of the fetal at birth among pregnant women who had taken supplementary standard folic acid during peri-conception period or only during the first trimester, were all better than those pregnant women who had not taken the standard folic acid supplements. After adjustment for potential confounders as gestational weeks, maternal age, mather's education level, results from the logistic regression showed that intake of standard folic acid supplements appeared a protective factor for those babies who were smaller than the gestational age (RR = 0.45, 95%CI: 0.24 - 0.86), at premature delivery (RR = 0.52, 95%CI: 0.32 - 0.87) or with low birth weight (RR = 0.39, 95%CI: 0.19 - 0.80). However, data from this study showed that provision of folic acid supplements to the pre-pregnant or at first trimester alone did not make obvious impact on those babies as prematured, small for gestational age and at low birth weight. CONCLUSION: Standardized provision of folic acid supplements during peri-conceptional period could improve the outcomes of birth.