The invention relates to the use of ITIH5 as a biomarker of endometrium receptivity to embryo implantation. Also provided are methods and kits for using this biomarker for detecting the receptivity state of the endometrium of a mammal to embryo implantation, for diagnosing infertility in a female mammal, for the early diagnosis of pregnancy, for detecting the window of embryo implantation in the endometrium of a female mammal, for in vitrofertilization of a female mammal, and for diagnosing endometriosis.
