Figure 1.

The gastrointestinal (gut) microbiota. During pregnancy, the gut microbiota undergoes profound changes with different enterotypes characterizing each woman. If abnormal bacterial translocation across the epithelium that is associated with increased levels of LPS occurs during early pregnancy, uterine innate immunity and obstetric outcome may be affected. Abnormally increased intestinal permeability during early pregnancy is associated with increased levels of circulating bacterial products and cytokines. Both events might increase inflammasome activation at the endometrial level; consequently, they increase the risk of obstetric complications during early pregnancy (figure created with BioRender.com).