Recent scientific studies have discovered that cells from the developing fetus cross the placenta during pregnancy, and the baby’s DNA becomes part of the mothers and can stay there for decades! The reverse is also true. Cells from the mother cross the placenta into the baby’s body and can be found many years later. (Cell Migration from Baby to Mother, Gavin S Dawe, Xiao Wei Tan, Zhi-Cheng Xiao). Fetal cells can also be shared from one pregnancy to another, meaning the cells of older siblings may live within younger siblings.
The scientific term for harboring cells that originated in a genetically different individual is called Microchimerism (“Chimera” in Greek Mythology is an animal made up of multiple animals).
Not only have these fetal cells been found in a mother’s body, but there is even evidence that they can target areas of disease. For example, there has been research to support that fetal cells battle certain heart conditions in a mother. Quite literally, your baby can mend your heart. Aww! And there is also evidence that fetal cells cross the blood barrier and generate neurons in the memory area of a mother’s brain. Could this be the scientific reason for “maternal instinct” or a “mother’s intuition?”
Some of our baby’s cells will circulate in our bloodstream, organs, hearts and brains long after our babies reach adulthood. They are a part of us…literally. Many of the fetus’ cells that enter our body are immune system cells, while some are stem cells. Around the time of your baby’s birth, it is estimated that 6% of the DNA in your blood plasma is the baby’s. Some of these cells remain long after and create their own rogue lineages within the mother’s body. This is part of the reason that skin and organ transplants between mother and child have a higher success rate than between father and child.
However, just like children, sometimes fetal cells can be mischievous! They have been known to increase the risk of certain cancers, autoimmune diseases and lupus while maternal cells aren’t so innocent either. They can potentially cause autoimmune problems in babies as well.
So, how much foreign DNA do we contain? Any baby we have ever conceived (even ones we have miscarried unknowingly), with half of those cells generated from the father, are a part of us now. Our mother’s cells are also in us. There are also studies that link intercourse with DNA michrochimerism as well. Yikes!
In a way, it is kind of comforting though to know that our babies will always be a part of us. I have always thanked my daughter for enhancing my life, and now I am even more grateful for the deep cellular relationship that we share.
Image Credit: Emma Whitney Photography