The presence of unusual natural killer cells in human endometrium has been recognized for 30 years. but despite considerable research effort. the in vivo role of uterine natural killer (uNK) cells in both normal and pathological pregnancy remains uncertain. uNK cells may differentiate from precursors present in endometrium. https://www.diegojavierfares.com/quick-find-Umpqua-U203-U-Series-Hook-clearance/