[Placental microbiota and pregnancy]

The role of microbes in regulating the metabolism and immune function of the body has been highlighted. The interactions of host-microbe and microbial-microbe have existed before the birth. However, the existence of placental microbiota and their regulatory effects on pregnancy are still controversial. It was found that placental microbes might be implanted into the placenta via urogenital-placental, gastrointestinal-placental, and oral-placental routes. Microbiome may play a role in promoting the outcome of benign pregnancy, and the placental microbiota in pathological pregnancy may be associated to adverse pregnancy outcome. Placenta and amniotic fluid microbes have been linked to abortion, chorioamnionitis, premature rupture of membranes, premature delivery and stillbirth in Cultivation-dependent and Cultivation-independent studies. Obesity, gestational diabetes mellitus, probiotics and antibiotics during pregnancy may be the main factors affecting placenta microbiology.