Association between Maternal Nutrition and Preterm Birth: A Scoping Review

Preterm birth is the leading cause of mortality in children globally under the age of 5 years. A universal, daily necessity, nutrition has potential for intervention to modulate preterm birth risk. This scoping review aimed to synthesize evidence on nutrition as an interventional tool to reduce preterm birth risk.

PubMed, CINAHL, Web of Science, Cochrane database, EMBASE and Google Scholar were searched for relevant studies published between the years of 2000-2023.

Inclusion criteria were human pregnancy populations with dietary intervention with intent of modulating preterm birth risk. Original research articles, cohort studies, cross-sectional studies and randomized control trials were included and papers with results not yet reported, non-original research articles and exposure or intervention not reported were excluded.

For this scoping review, databases were searched using the Problem, Concept, Context (PCC) framework (Problem: Spontaneous preterm birth; Concept: nutrition; Context: Antenatal period). Data was analyzed, risk of bias assessed, and evidence was summarized based on results.

From 1,664 citations, data were extracted from 74 studies. Studies were divided into three categories and below recommendations are presented from results: 1) Micronutrient recommendations (15 studies): Iron 60mg oral, folic acid 0.4mg oral daily and daily multiple micronutrient supplement have strong evidence as protective factors against preterm birth. 2) Macronutrient recommendations (24 studies): docosahexaenoic acid supplementation >800mg oral daily throughout pregnancy, most importantly, from the second trimester to delivery and moderate fish intake of ∼3 servings weekly has strong evidence as protective against preterm birth. 3) Specific-diet recommendations (35 studies): Diets high in fruits, vegetables, oils, whole grain cereals and fiber, adherence to the Mediterranean diet and avoidance of the Western diet demonstrate decreased preterm birth risk.

Nutrition plays an important role in preterm birth. Synthesis of evidence on dietary behavior is useful for women, their healthcare providers, alongside the legislators and regulatory bodies that support them.