The role of intestinal microbiota on pre-eclampsia: Systematic review and meta-analysis

Abstract

Aim: To investigate differences between gut microbiota diversity and composition of healthy pregnant women and women with pre-eclampsia (PE).

Methods and results: This is a systematic review and meta-analysis of the literature, in which the terms "pre-eclampsia", "gastrointestinal microbiome" and "pregnant women" were used to search MEDLINE (PubMed), BVS (LILACS and others), Embase (Elsevier) and Cochrane Library, including observational studies and case-control that investigated changes in the gut microbiota during pregnancy. Six studies were included, with 479 pregnant women. A significantly lower gut microbiota alpha diversity measured as the Shannon index was found in pregnant women with PE in comparison with healthy controls (SMD: -0.47; 95 %IC: -0.77 to -0.18; P = 0.02; I² = 0 %; three studies, 179 participants), while no significant differences were found in the relative abundance of Bacteroidetes, Firmicutes, Actinobacteria, and Proteobacteria, despite significant differences reported in the individual studies.

Conclusion: Pregnant women with PE have lower gut microbiome diversity, however, there is insufficient evidence to determine whether there are changes in gut microbiota composition.

Significance and impact of the study: The gut microbiota can be a new treatment target to try to prevent changes in maternal bacterial proportions, aiming to reduce complications during pregnancy.

Keywords: Gastrointestinal microbiome; Microbiota; Pre-eclampsia; Pregnant women; Systematic review.