top of page

Mothers Instinct?

Ever wonder how mothers can sense something wrong with their children? The key to the answer might be in the incredible phenomenon known as fetal-maternal microchimerism. The process by which the mother and her unborn fetus bidirectionally exchange maternal, fetal, and placental cells. Learning about microchimerism has huge significance to science in learning more about autoimmune diseases, cancer, and wound healing. [Shrivastava, et al. 2019]

How do we know?  [C. Rijnink, et al. 2015] tested the levels of Y chromosomes in several different autopsy tissues- the heart, liver, lungs, etc.- from 26 pregnant women who had died whilst pregnant or one month after giving birth to a son. The results showed detection of the Y chromosome in all tissue types, presenting strong evidence for the possibility of fetal microchimerism. Y chromosomes are detected through PCR amplification of Y chromosomes and DNA probe fluorescent markings [Shrivastava, et al. 2019] The mechanism by which this happens is unexplained across scientific research, however, there is much speculation as to why. The evolutionary perspective explains how an increase in fetal progenitor cells is used to aid the survival of the fetus. For examples, cells found in thyroid increase the chances of survival by upregulating heat production, whilst cells in the breasts Increase milk production. [M. Bodyy et al. 2015] discusses this as well as the conflicts between fetal microchimerism and maternal health in their article.

[Shrivastava, et al. 2019] outline the role of microchimerism in a variety of phenomena. They suggest that fetal microchimerism may have a link to the presentation of autoimmune diseases. Women more predominantly are susceptible to autoimmune diseases so there’s likely a uniquely female experience that causes this. They also list several autoimmune diseases in which the Y chromosome was present decades after pregnancy. This included Hashimoto’s thyroiditis where the thyroid becomes unactive when antibodies are made to attack the thyroid. This causes symptoms of weight gain, fatigue, goiter (enlargement of thyroids) and muscle weakness. [Shrivastava, et al. 2019] Explain how fetal cells can have both a positive and negative effect. Regarding cancer, fetal stem cells can take an immunosurveillance role where they survey malignant cell formation and then repair tissue in turn. For instance, fetal cells have been found at the site of lung tumors decades after pregnancy whilst also being present in quantities several fold higher than in normal lung tissue.

Image showing how Hashimoto’s disease affects the thyroids [Cleaveland Clinic, 2023]

Fetal-Maternal microchimerism is an incredible phenomenon which holds the key to the answer to a lot of our questions regarding autoimmune diseases and cancer. The answer to how it’s caused, and how it’s treated lies with fetal-maternal microchimerism. The bidirectional exchange of fetal and maternal cells across the placenta can be identified decades after a pregnancy; current research looks at how this microchimerism affects genome hereditary.


Links to Sources


26 views0 comments


bottom of page