Our findings illustrate that there is a greater nuclear translocation of the NF-κB protein p65 in chorionic villi and deciduas from women with early spontaneous miscarriage, but a significant increase was observed in villous stromal cells, decidual glandular epithelial cells, decidual stromal cells and decidual vessel endothelial cells compared to viable pregnancies. This evidence concerns the gene NFKB1 and spontaneous abortion.