The theory would be that if you have high natural killer cells, you’re either at a higher risk of miscarriage or you’re at a higher risk of recurrent implantation failure which is you’re putting back multiple good quality blastocysts over several cycles and still not getting pregnant. If you’re diagnosed with uterine high natural killer cells, there are different treatment options depending on what clinic you go to. The most common approach is to give you pregnazole which will reduce the amount of natural killer cells and theoretically improve your chances of implantation and reduce your chances of miscarriage but the evidence is probably weak at best and again should only be done by sort of a center that specializes in that kind of area.
Accumulating data suggests that the mechanisms underlying recurrent pregnancy loss are driven by immunological dysfunction. In the literature, repeated implantation failures and recurrent pregnancy losses, although pathophysiologically and immunologically different, tend to overlap. Studies have shown that distinct uterine NK cell populations might promote pro-inflammatory rather than anti-inflammatory pathways that could result in poor obstetric outcomes. In women suffering from recurrent pregnancy loss this secretion of Interleukin-10 inhibits (IL-10) and interferon gamma, was decreased due to a general decrease of decidual NK cells. Moreover, an increase in the number of decidual NK cells is also noted in such cases. A metanalysis has illustrated the increased percentage of peripheral NK cells in women with recurent pregnancy loss underlying that any abnormality in their number could potentially cause miscarriage. The decidual NK cells through the regulation of immune response, create an immunosuppressive environment favouring the placental invasion and the viability of the gestation. Any disturbance or disruption of their normal function in any pregnancy could lead to adverse reproductive outcomes.
