The gut microbiome in pregnancy and pregnancy complications

During gestation, the female body undergoes a number of changes; accordingly, her microbiota also undergoes marked changes throughout the duration of her pregnancy. Some shifts in the microbial community are imprinted even before pregnancy and may affect a woman's ability to conceive. Prepregnancy obesity and inflammatory bowel disease are associated with gestational dysbiosis, as are several conditions occurring during pregnancy, including gestational diabetes mellitus and preeclampsia. Here, we review pregnancy and associated complications in the context of the gut microbiota, but dysbiosis in other microbial communities, including those of the vagina, oral cavity, and cervix, is also associated with pregnancy-related conditions. We not only highlight the numerous studies conducted thus far but also discuss some of the shortcomings in the field and provide important directions for future research.