An article on LifeSiteNews makes the claim that a fetus is not only not a parasite, but is actually helping to contribute to the health of the mother by exchanging cells with her. Yes, you read that correctly - that unformed mass of tissue is actually providing the mother with beneficial cells which may stay with her for the rest of her life! According to studies which have been going on for more than 30 years, there is a give-and-take process that happens in the placenta, where the mother shares her cells with the fetus, and the fetus shares its cells with the mother. These fetal cells have been observed aiding the mother's immune system by increasing her autoimmune defenses. Further, the child's stem cells also enter the mother's bloodstream, helping to regenerate many things, not the least of which are her heart, liver, and brain. One study goes on to posit that that at the end of a pregnancy, 6% of the DNA in the mother's blood comes from her baby!