At 18 d, 32 DEGs involved in pregnancy and miscarriage were identified, such as LILRA4, LILRA6, leukocyte immunoglobulin-like receptor subfamily B member 3, leukocyte immunoglobulin-like receptor subfamily A member 6, DNA-directed RNA polymerase I subunit RPA12, CDH2, natural cytotoxicity triggering receptor 1, Bos taurus 2′,5′-oligoadenylate synthetase 1 (OAS1Y, 40/46kDa), and carbonic anhydrase 5A; in addition, the importance of CDH2 on embryo implantation was emphasized by previous study [24]. This evidence concerns the gene CA5A and spontaneous abortion.