Why are Pregnant Women So at Risk for Listeria Infections?
One theory is that in pregnancy, the immune system is suppressed so the body doesn’t reject the embryo and fetus. This reduction in immunity may be why these women are so susceptible to listeriosis and why the complications can be so severe. Researchers at Berkeley, however, discovered that Listeria monocytogenes bacteria use the immune system suppression to invade the placenta where they are protected from the mother’s immune system.
Once the bacteria are in the placenta, they can grow rapidly, then emerge to infect the maternal liver and spleen. One theory is that miscarriage occurs as a defense mechanism so the body is protected from the source of the bacteria’s growth. It is difficult for any bacteria to cross the placental barrier, but once they do, complications can be very serious. Scientists think that the bacteria can cross the endothelium of the maternal blood vessels, and get into the fetal circulatory system of the placental villi.
Listeria May be Serious Miscarriage Threat in Early Pregnancy
New research conducted at the University of Wisconsin-Madison and published in the journal mBio has found that Listeria monocytogenes food poisoning can be a serious miscarriage threat in early pregnancy. Scientists at the university’s School of Veterinary Medicine studied how pathogens affect fetal development and change pregnancy outcomes.
