Maternal probiotic supplementation and effects on the fetal placenta

Increasing number of pregnant women are consumi ng probiotics to promote their own health and that of their unborn fetuses. Such supplements are presumed to be safe for pregnant mothers and their unborn offspring. For pregnant mothers, such bioactive compounds might lower the risk of constipation, diarrhea, other gastrointestinal conditions, and pre-term birth, and prevent adverse pregnancy outcomes, including gestational diabetes mellitus and depression/anxiety. More research is needed to examine potential safety of probiotic consumption during pregnancy and long-term health consequences to offspring. The conceptus can also be indirectly affected by maternal probiotic supplementation through microorganism production of bioactive compounds. The placenta is in direct communication with the underlying uterine tissue. Thus, compounds in the maternal blood can easily transfer across the placenta and impact this hormonally sensitive organ. Select studies suggest that disruptions to the maternal microbiome dramatically affect the placenta. In the current review, we will therefore consider the evidence to date of how maternal probiotic supplementation affects the placenta. Three potential mechanisms we will explore include the possibility that maternal probiotic supplementation might impact the putative placenta microbiome. The second potential mechanism we will consider is that maternal probiotic consumption alters bacterial-derived metabolites, including short-chained fatty acids, polyamines, Vitamin B9, and Vitamin B12. The third potential mechanism to be discussed is that such supplements affect maternal and placental immune responses. Before probiotics are promoted for healthy pregnant women and those with gestational disorders, more studies, including those examining the effects on the placenta, are essential.