NK cell values are between 7 and 40. The normal value range is suitable for pregnancy. Natural killer cells are inhibitory multifunctional immune cells that have a regulatory effect on a wide range of cells in the body, and are not only associated with anti-tumor and anti-viral infections, but are also involved in hypersensitivity reactions. Under normal circumstances, NK cells will be in a dormant state, and will only increase when examined in the presence of viral infections or tumors in the body. However, an increase in NK cells will lead to an imbalance of the immune system in the patient’s body, thus affecting the patient’s ability to conceive and lowering the chances of pregnancy. Therefore, for people with high natural killer cell counts, it is recommended that they undergo targeted treatment under the guidance of a doctor and prepare for pregnancy when the counts are controlled within the normal range.