Conversely, disorders of pregnancy in mothers carrying a C2/C2 fetus and expressing KIR2DL1 on uterine NK cells have been interpreted as being due to stronger inhibition by KIR2DL1, resulting in decreased activation of specialized uterine NK cells that promote vascular remodeling to increase blood supply to the fetus (10, 11, 36, 37). This evidence concerns the gene KIR2DL1 and pregnancy.