Association of maternal pre-pregnancy dietary intake with adverse maternal and neonatal outcomes: A systematic review and meta-analysis of prospective studies

Abstract

This study aimed to summarize the evidence regarding the effects of dietary intake before conception on pregnancy outcomes by performing a systematic review and meta-analysis of prospective studies. Electronic databases were searched from inception up to August 2021. Overall, 65 studies involving 831 798 participants were included and 38 studies were quantitatively pooled. With regard to maternal outcomes, pre-pregnancy intake of fried food, fast food, red and processed meat, heme iron and a low-carbohydrate dietary pattern was positively associated with the risk of gestational diabetes mellitus (GDM) (all P < 0.05). However, a high dietary fiber intake and folic acid supplementation were negatively associated with GDM risk (both P < 0.05). With regard to neonatal outcomes, maternal caffeine intake before pregnancy significantly increased the risk of spontaneous abortion, while folic acid supplementation had protective effects on total adverse neonatal outcomes, preterm birth, and small-for-gestational age (SGA, all P < 0.05). However, no significant associations were found between adverse pregnancy outcomes (i.e., GDM and SGA) and the pre-pregnancy dietary intake of sugar-sweetened beverages, potato, fish, and carbohydrates and the Healthy Eating Index. Our study suggests that maintaining a healthy diet before conception has significant beneficial effects on pregnancy outcomes.

Supplemental data for this article is available online at https://doi.org/10.1080/10408398.2021.1989658

Keywords:

• Pre-pregnancy diet
• maternal outcome
• neonatal outcome
• meta-analysis

Acknowledgments

The authors’ responsibilities were as follows: F.F.Z. and D.H.W. contributed to the conception and design of the systematic review and meta-analysis. Y.F.C., M.Q.L., and A.H.X. completed the literature search and data extraction and quality assessment. Y.F.C. and M.Q.L. performed the statistical analyses. Y.F.C. and M.Q.L. drafted the manuscript. G.D.C. and J.L. assisted in the revision of the manuscript. All authors read and approved the final manuscript.

Disclosure statement

There are no relevant financial or non-financial competing interests to report.

Funding

This work was supported by the Medical Scientific Research Foundation of Guangdong Province, China (No. A2020582) and the National Natural Science Foundation of China (No. 81602853).

Data availability statement

The Data Supporting The Findings Of This Study Are Available Within The Article And Its Supplementary Materials.