ArticleBMC pregnancy and childbirth2015
Folic acid supplementation, preconception body mass index, and preterm delivery: findings from the preconception cohort data in a Chinese rural population.
Article in BMC pregnancy and childbirth, 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 10 papers, 1 of them a synthesis that pooled it.
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10 citing papers in PubMed, 1 synthesis or guideline pooled it, 32 citations in OpenAlex.
- Maternal body mass index and risk of neonatal adverse outcomes in China: a systematic review and meta-analysis.BMC pregnancy and childbirth · 2019Pooled it
- Preconception Folic Acid Supplementation Associated with Attenuated Effects of Air Pollution on Birthweight Outcomes.Environment & health (Washington, D.C.) · 2026Article
- Association between inflammatory indicators derived from preconception complete blood count and specific adverse fetal, neonatal, and pregnancy outcomes: a national cohort study.Frontiers in endocrinology · 2026Article
- Association of nutrient intake and dietary patterns with serum folate and anemia-related biomarkers in Taiwanese pregnant women with pre-pregnancy overweightness or obesity.International journal of medical sciences · 2025Article
- Evaluating the progression to abnormal thyrotropin in euthyroid preconception women: a population-based study.Thyroid research · 2024Article
- Joint effect of maternal pre-pregnancy body mass index and folic acid supplements on gestational diabetes mellitus risk: a prospective cohort study.BMC pregnancy and childbirth · 2023Article
- Association of Preconception Thyrotropin Levels With Fecundability and Risk of Spontaneous Abortion in China.JAMA network open · 2022Article
- Preconception Thyrotropin Levels and Risk of Adverse Pregnancy Outcomes in Chinese Women Aged 20 to 49 Years.JAMA network open · 2021Article
- Essential Mineral Intake During Pregnancy and Its Association With Maternal Health and Birth Outcomes in South East Queensland, Australia.Nutrition and metabolic insights · 2019Article
- The prevalence and risk factors of preterm small-for-gestational-age infants: a population-based retrospective cohort study in rural Chinese population.BMC pregnancy and childbirth · 2017Article
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Authors and funding
9 authors at 2 institutions in 1 country.
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No grant is acknowledged in the PubMed record.
Abstract
backgroundFolic acid (FA) supplementation before and during the first trimester can reduce the risk of occurrence of preterm delivery (PTD). Preconception body mass index (BMI) is also associated with PTD. This study aimed to investigate the combined effect of FA supplements and preconception BMI on the risk of PTD.
methodsThe data of a cohort from 2010-2011 that was obtained through a preconception care service in China was used (including 172,206 women). A multivariable regression model was used to investigate the association between maternal preconception conditions and the risk of PTD. The interaction of preconception BMI and FA supplementation was measured by a logistic regression model.
resultsTaking FA supplements in the preconception period or in the first trimester reduced the risk of PTD (odds ratio [OR] = 0.58 and OR = 0.61, respectively). Women with an abnormal BMI had an increased risk of PTD (OR = 1.09, OR = 1.10, and OR = 1.17 for underweight, overweight, and obese, respectively). Preconception BMI showed an interaction with the protective effect of FA supplementation for PTD. With regard to the interaction of FA supplementation, the adjusted odds ratio (aOR) was 0.57 (95% CI: 0.51, 0.64) in underweight women, 0.85 (95% CI: 0.73, 0.98) in overweight women, and 0.77 (95% CI, 0.65, 0.91) in obese women. Preconception BMI also showed an interaction with the time of FA supplementation. Women with a normal BMI who began to take FA supplements in the preconception period had the lowest risk of PTD (aORs: 0.58 vs. 0.65 beginning in the first trimester). The aORs at preconception and the first trimester in the underweight group were 0.56 vs. 0.60. The aORs at preconception and the first trimester were 0.94 vs. 0.65 and 1.15 vs. 0.60 in the overweight and obesity groups, respectively.
conclusionsIn our study, FA supplements reduced the risk of PTD, while abnormal BMI raised the risk of PTD, although higher BMI categories did not have this higher risk once adjusted analysis was conducted. The protective effect of FA supplementation for PTD was reduced in women with overweight or obesity. To get better protection of FA supplementation, women with normal BMI or underweight should begin to use in preconception, while women with overweight or obesity should begin to use after conception.
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