- Some types of infertility may be caused by a slightly overactive immune system. When this occurs the immune system can attack egg, sperm, embryo and even a developing fetus. This can result in difficulty achieving pregnancy, maintaining the pregnancy, or repeated miscarriages.
Natural killer (NK) cells are regulated by the immune system. In women who have autoimmune issues, the NK cells can react abnormally to an implanting embryo, treating it as an invading cell and signalling for the body to attack it.
What are Natural Killer Cells?
Natural killer (NK) cells are sub variety of the white blood cells it’s the basis for the body’s defense mechanism. They fight and safeguard the body against harmful tumors, infections and bacteria etc. It’s important to observe the role of NK cells when the body is normal and when it’s affected by disease. It’s amazing to know that each organ in our body has NK cells to protect the organ, and the womb has the most NK cells. Here, NK cells play their role to support the blood supply for the development of the foetus, and to detect if any foreign cells are entering into the body from the father’s cells or egg donations if they are body-friendly. However, if the count of NK cells is more than normal, they are destructive. They impact negatively and begin to attack rather than safeguarding the pregnancy, and leads to abortion or miscarriage. In few cases, extremely high levels of NK cells do not allow the implantation to happen.
As we know that the improper functioning of NK cells leads to a miscarriage, many health clinics conduct blood tests to track the NK cells which circulate in the bloodstream. If the rate is high or abnormal some medications and steroids, intravenous immunoglobulins are given which obstruct the fallopian tubes. With the advancements in technology and treatments which focus on NK cells in women which contribute to the failure of pregnancy, its misfortune that science is not able to handle it
Uterine natural killer cells
NK cells are a powerful kind of immunity cells which occupy in the uterine mucosa while the placenta is being formed in the uterus. Also these NK cells occur in non pregnant women which exist in the endometrium and they are actively supervised by the female ovarian hormones. Once the ovulation takes place, the NK cells growth at a tremendous speed contributing to 30% of endometrial stroma. After ovulation they rapidly grow in count and gather where the implantation happens, and interact closely with the placenta cells which convert the arteries to conductance vessels. Its significant that this conversion takes place as it supplies proper blood flow to the growing fetus in the uterus.
Testing of NK Blood cells
Immunity cells play an important role in the immunity system to check early signs of any viral or infectious and cancer cells that might be present in the uterus which obstruct the process of implantation. Hence its utmost important to check the NK cells in blood flow for women who experience often miscarriage.the tests results reveal that women who have recurrent miscarriages have high levels of NK cells in the uterine which hinder the successful implantation. The percentage of NK cells for an individual differ anywhere from 5% to 29%. The presence of NK cells exceeding levels of 12% leads to miscarriage and can be treated.The presence of NK cells exceeding levels of 12% leads to miscarriage and can be treated. The percentage of the level of NK cells that exist in an individual depend on several factors such as age, stress levels etc. The tests for presence of NK cells results vary in different labs. Also NK cells present in the uterine have significantly lower cytolytic life compared to NK cells present in the bloodstream. However there is no scientific evidence that the percentage level or existence of NK cells which leads to miscarriages.