Composição da microbiota intestinal de gestantes e sua influência na ocorrência de desfechos perinatais adversos: revisão sistemática

Abstract

During the gestational period, the intestinal microbiota has been shown to be a crucial factor for maternal-fetal health, playing a direct role in proper nutrient absorption, the gut-brain connection, and influencing metabolic processes. Furthermore, studies indicate that the intestinal microbiota may regulate fetal growth or suggest the type of delivery, bringing risk of perinatal outcomes for the gestational period. Therefore, the aim of this study is to evaluate the relationship between the composition of pregnant women's intestinal microbiota and the occurrence of adverse perinatal outcomes through a systematic review. The research was conducted using databases and platforms such as PubMed, Embase, Lilacs, Scopus, and Web of Science. Eligibility criteria included studies that assessed the intestinal microbiota of pregnant women, regardless of health conditions, in English, Portuguese, or Spanish, excluding interventions, randomized clinical trials, animal or in vitro studies, conferences, and works in other languages. Furthermore, a formal protocol was registered in the PROSPERO registry (registration number CRD42023470580). The methodological quality of the selected studies was assessed based on the Joanna Briggs Institute Reviewers' Manual. After the search, a total of 6546 articles were identified, with twelve studies selected, the studies had a sample size ranging from 16 to 1,479 women, with participants' chronological age between 20 and 40 years. Most of the included studies used genetic extraction of nucleic acids. As for the results, eight perinatal outcomes were identified, including abortion, gestational weight gain, fetal abdominal circumference, intrauterine growth, femur length, weight, head circumference, and preterm birth, which were associated with more than thirty intestinal strains, such as those from the families Eubacteriaceae, Lachnospiraceae, Ruminococcaceae, Parabacteroides, and Porphyromonadaceae, and the genera Streptococcus. According to the adopted quality criteria, it was identified that more than 80% of the analyzed articles were classified as good quality. The role of the microbiota on perinatal outcomes is reinforced by these findings, however, to fully understand the interactions between perinatal complications and maternal intestinal microbiota, standardizing methodologies and further research development are necessary.