The gut-reproductive axis: Bridging microbiota balances to reproductive health and fetal development

The gut microbiota is a highly complex microbial community residing in the digestive tract of humans and animals, closely linked to host health. Dysbiosis within the gut microbiota has been associated with various diseases. Moreover, it interacts with the female reproductive system's microbiota, influencing maternal reproductive homeostasis. Although the gut microbiota holds potential for treating reproductive system diseases and modulating offspring fertility, research in this domain remains limited. This review examines the relationship between both balanced and imbalanced gut microbiota and reproductive system diseases, as well as their effects on fetal development. It is highlighted that dysbiosis in the gut microbiota may contribute to several reproductive conditions, including polycystic ovary syndrome (PCOS), preeclampsia (PE), endometriosis, gestational diabetes, and reproductive cancers. The abundance of specific gut microbial species or interactions among various species can influence the reproductive system through hormonal pathways and other mechanisms, ultimately affecting pregnancy outcomes and fetal health. Therefore, the concept of the gut-reproductive axis is proposed, emphasizing the significant role of maternal gut microbiota in shaping fetal development, metabolic capacity, and immunity.