Glucose is a vital fuel for fetal growth, and carbohydrates are the primary source of glucose in the diet. The effects of carbohydrate intake during pregnancy on neonatal birth weight have not been fully investigated or systematically reviewed. Therefore, this systematic review aimed to collate the available evidence to determine whether carbohydrate intake during pregnancy impacts newborn birth weight. A literature search was performed from inception to March 2022 in Embase, Medline, and PsycInfo. Articles published in English were independently screened for the title and abstracts, and then for full texts. Out of 17 studies included, a significant relationship between the intake of maternal carbohydrate or its subcomponents and neonatal birth weight was reported in six studies. Of them, one study reported that higher carbohydrate intake in early pregnancy was associated with lower birth weight. The two other studies reported a positive correlation between maternal carbohydrate intake and neonatal birth weight regarding first- and second-trimester intake. Maternal carbohydrate intake may have an impact on birth weight, as suggested by the included studies in this systematic review. However, the overall review indicates contradictory findings concerning the relationship between carbohydrate intake and neonatal birth weight. Studies assessing the type of carbohydrate and the amount consumed with improved methodological quality are recommended.
Keywords: birth weight; carbohydrate intake; macronutrients; maternal nutrition; systematic review.