The association between maternal fruit consumption before and during pregnancy and fetal growth: The Lanzhou birth cohort study

Background: The association between maternal fruit consumption and fetal growth remains inconsistent. The current study aimed to determine whether maternal fruit consumption was associated with low birth weight (LBW) or small for gestational age (SGA) babies. Methods: A large birth cohort study was conducted in Lanzhou, China, from 2010 to 2012 and included 10,076 pregnant women at the 1st, 2nd, and 3rd trimester of pregnancy for analysis. Fruit consumption in the 1st, 2nd, and 3rd trimester of pregnancy was measured by a self-designed food frequency questionnaire (FFQ) and divided into three groups: 1) inadequate fruit consumption: <200 g/d for the1st, 2nd, and 3rd trimester; 2) adequate fruit consumption: 200-350 g/d for the 1st trimester or 200-400 g/d for the 2nd and 3rd trimester; 3) excessive fruit consumption: >350 g/d for the 1st trimester or > 400 g/d for the 2nd and 3rd trimester. A case-control study was used to analyze the association between fruit intake during pregnancy and low birth weight infants. Results: Compared to adequate fruit consumption, excessive fruit consumption throughout each trimester of pregnancy was associated with a lower risk of LBW, with an odds ratio (OR) ranging from 0.70 to 0.79 (95 % confidence interval, CI: 0.57-0.98); while inadequate fruit consumption was associated with a higher risk of infant LBW, with an OR ranging from 1.26 to 1.36 (95%CI: 1.04-1.66). After stratifying by mother's pre-pregnancy body mass index (BMI), the results were similar among women with underweight BMI. No significance was found between fruit consumption and SGA in the general population. Still, stratified analyses showed that inadequate fruit consumption was associated with an increased risk of SGA in underweight mothers, with an OR ranging from 1.66 to 1.79 (95%CI: 1.13-2.64). Conclusions: Fruit consumption during pregnancy reduces the risk of LBW in Chinese women, especially in women with low pre-pregnancy BMI.