The placenta is a highly complex biological organ. It allows blood to
flow from mother to baby, and back again. The mother's blood and the
baby's blood are filtered through the placenta, but they never actually
mix. The placenta has an important role in hormone production as well. It
also protects the fetus from harmful bacteria and infections.
Problems
with the placenta can affect the developing baby's growth. The baby
cannot grow and develop normally in the womb if it does not get enough
oxygen and nutrients. This increases the chances of complications during
pregnancy and delivery.