Author/Authors :
Shao, Yawen Gansu Provincial Maternity and Child Care Hospital - Lanzhou - Gansu, China , Mao, Baohong Gansu Provincial Maternity and Child Care Hospital - Lanzhou - Gansu, China , Qiu, Jie Gansu Provincial Maternity and Child Care Hospital - Lanzhou - Gansu, China , Bai, Yan Gansu Provincial Maternity and Child Care Hospital - Lanzhou - Gansu, China , Lin, Ru Gansu Provincial Maternity and Child Care Hospital - Lanzhou - Gansu, China , He, Xiaochun Gansu Provincial Maternity and Child Care Hospital - Lanzhou - Gansu, China , Lin, Xiaojuan Gansu Provincial Maternity and Child Care Hospital - Lanzhou - Gansu, China , Lv, Ling Gansu Provincial Maternity and Child Care Hospital - Lanzhou - Gansu, China , Tang, Zhongfeng Gansu Provincial Maternity and Child Care Hospital - Lanzhou - Gansu, China , Zhou, Min Gansu Provincial Maternity and Child Care Hospital - Lanzhou - Gansu, China , Xu, Xiaoying Gansu Provincial Maternity and Child Care Hospital - Lanzhou - Gansu, China , Yi, Bin Gansu Provincial Maternity and Child Care Hospital - Lanzhou - Gansu, China , Liu, Qing Gansu Provincial Maternity and Child Care Hospital - Lanzhou - Gansu, China
Abstract :
Background: To evaluate the independent and collective effects of maternal iron supplementation and dietary iron intake upon the risk of moderate preterm birth and its subtypes.
Methods: In this birth cohort study, 1019 pregnant women with moderate preterm birth and 9160 women with term birth were recruited at Gansu Provincial Maternity and Child Care Hospital from 2010-2012 in Chi-na. Unconditional logistic regression models were utilized to evaluate the association between maternal iron supplementation, dietary iron intake, and the risk of moderate preterm birth and its subtypes.
Results: Compared with non-users, iron supplement users exerted a protective effect upon the overall (OR=0.54, 95%CI=0.40-0.72) and spontaneous moderate preterm birth (OR=0.39, 95%CI=0.33-0.83). Com-pared with the 25th quartiles of dietary iron intake, either before or during pregnancy, it exerted a significantly protective effect upon those who had the highest quartiles of dietary iron intake (OR=0.87, 95%CI=0.82-0.95 for the highest quartiles of dietary iron intake before pregnancy OR=0.85, 95%CI=0.79-0.91). Positive associa-tion was observed between the additive scale and multiplicative scale for preterm birth, spontaneous preterm rather than medically indicated preterm.
Conclusion: Iron supplements (60 mg/day) and high-iron intake (>25.86 mg/day before pregnancy, >30.46 mg/day during pregnancy) reduced the risk of moderate preterm birth. Positive correlation is found between the additive scale and multiplicative scale for preterm birth, spontaneous preterm birth.
