Fetal microchimerism is a fascinating biological phenomenon that takes place between pregnant mothers and their children. It helps bond them physically and emotionally and often aids maternal health. In some instances, however, it has also been attributed to increased risk for certain diseases in women.
What is Fetal Microchimerism?
Once considered rare, through various research and studies, fetal microchimerism is now believed to exist in all pregnant women and can stay within mothers for decades. This biological phenomenon occurs when small amounts of genetically different cells are transferred from one person to another. Scientists believe microchimerisms happen in blood transfusions and organ transplants, but it is most common in pregnancy when small numbers of fetal cells are transferred to a pregnant woman.
Maternal cells can also be transferred to the preborn baby, particularly impacting the development of the child’s brain and immune system.
There are two types of microchimerisms during pregnancy: fetal microchimerism (when fetal cells transfer to the mother) and maternal microchimerism (when cells from the mother transfer to her preborn baby).
“The situation is more complex” because a preborn baby can acquire fetal cells from its mother that she “acquired during a previous pregnancy,” according to authors of an article on Science Direct.
Mother’s Cells Aid in Preborn Development
Maternal microchimerism may aid in the developing baby’s immunity. A mother’s antibodies also protect her child. They are generated by her immune system and delivered to her preborn baby by the placenta while she is pregnant, and then after birth, a child can still receive them through the mother’s breast milk, helping protect the infant from pathogens.
The sharing of cells appears to help bond mother and child emotionally as well as physically.
“There is evidence that these fetal cells can even integrate into and influence the maternal brain,” stated Jennifer Wright, MD, in her article “Maternal-Fetal Bonding.” “There is an ongoing development of maternal-fetal bonding that tends to strengthen and mature throughout the pregnancy.”
Induced abortion doesn’t ‘cut the cord,’ so to speak, between a woman and her preborn child. “This exchange of cells occurs very early in pregnancy and is actually increased in instances of induced abortion,” wrote Dr. Wright.
The cell-sharing between mother and developing child influences both of them psychologically and physiologically.
Benefits of Fetal Microchimerism and Maternal Microchimerism
Fetal microchimerism and maternal microchimerism benefit the mother and her preborn child. Studies show cell transference usually begins between the fourth and sixth week in a woman’s pregnancy and increases significantly throughout her pregnancy, “reaching its maximum level in the days before childbirth.”
Maternal health benefits of fetal microchimerism include cell replacement, fighting lung, breast, and other cancers, and helping with tissue repair and regeneration, including healing after a C-section. Fetal cells have been discovered in different maternal tissues and organs, including skin, spleen, heart, kidney, brain, and thyroid.
Concerns about Fetal Microchimerism
“Pregnancy alters symptoms of autoimmune diseases,” wrote Matti Miller in her 2020 research paper, “The Effects of Fetal Microchimerism on Maternal Health.” “The risk of developing an autoimmune disease in parous women is higher after the first year postpartum. Fetal cells in the thyroid may contribute to thyroid cancer risk or susceptibility to other thyroid diseases.”
Matti also attributed that fetal microchimerism might be cause for some cancer concerns in women, including lung cancer. However, it may also play a strong role in fighting breast and ovarian cancer.
The Mystery Remains
Fetal and maternal microchimerism remain a fascinating phenomenon. As Miller concluded in her paper, “Fetal microchimerism has potential implications for the understanding of women’s health and disease pathology postpartum.”
The biological mystery of helpful versus harmful effects continues to help various research studies to garner greater understanding about maternal health even after birth.
Conclusion
Fetal microchimerism remains a profound and intriguing biological phenomenon that illustrates the deep connection between mother and child, extending far beyond birth. The exchange of cells during pregnancy not only strengthens the emotional and physical bond but also plays a critical role in maternal health.
As research continues to unravel this biological mystery, one thing is clear: the enduring link between mother and child is more intricate and powerful than ever imagined, offering new insights into maternal health and the lifelong impact of pregnancy.
