Microbiome, autoimmunity, allergy, and helminth infection: The importance of the pregnancy period.

Pregnancy is a special physical period in reproductive age women, which has a beneficial influence on the course of certain autoimmune diseases. It has been recently suggested that the microbiome undergoes profound changes during pregnancy that are associated with host physiological and immunological adaptations. The maternal microbiome remodeling during pregnancy is an active response of the mother, possibly to alter immune system status and to facilitate metabolic and immunological adaptations, which are needed for a successful pregnancy. In this review, we attempt to discuss (i) the role of maternal microbiome in pregnancy outcomes known to adversely influence neonatal and infant health, including preterm birth, cardiometabolic complications of pregnancy, and gestational weight gain; (ii) the association of microbiome with autoimmunity, allergy diseases, and asthma during pregnancy; and (iii) the impact of helminth infection during pregnancy.