Detailed analysis of peripheral blood natural killer (NK) cells in women with recurrent miscarriage

BACKGROUNDIncreased peripheral blood natural killer (NK) cell activity has been associated with unexplained reproductive failure including recurrent (three or more) miscarriages (RM). Studies have reported abnormalities in both numbers (absolute and proportion) and activation. This study assessed numerous NK cell parameters to determine which (if any) are altered in women with RM compared with controls, which parameter best differentiated women with RM from controls, and what NK levels should be considered high.