Functions of uNK cells in endometrium of subfertile and infertile women

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Tiinçe Aksak


Infertility is defined as the lack of ability to get pregnant within one year despite unprotected sexual intercourse. The endometrium is the inner layer of the uterus where the blastocyst attaches and grows. The content of the endometrium and the number of immune system cells therein can be associated with infertility. Most of the lymphoid cells found in the endometrium are uterine natural killer (uNK) cells. This has drawn attention to the immune system in infertility. However, the roles of uNK cells have not yet been fully elucidated. Studies suggest that uNK cells, members of the lymphoid system, may act an important role in implantation and pregnancy. Although the high number of these cells, which are important for implantation and the continuation of pregnancy, is associated with infertility, there are also studies suggesting that there is no relationship between them. In our study, it was aimed to investigate studies examining the relationship of uNK cells with subfertility and infertility.  Although peripheral NK cells fight tumor and virus-infected cells, it has been shown that uNK cells do not fight with trophoblasts, they take part a role in the invasion and vascularization process, and their number increases in early pregnancy.

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Aksak, T. . (2023). Functions of uNK cells in endometrium of subfertile and infertile women. Advanced Engineering Science, 3, 78–84. Retrieved from


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Aksak, T. (2023). The role of uterine natural killer (uNK) cells in the endometrium of infertile women. Advanced Engineering Days (AED), 6, 38-41.