The importance of uterine glandular secretions in embryo implantation is highlighted by the infertility of the sheep uterine gland knockout model (Spencer and Gray, 2006) and murine knockout and pharmacological intervention models of glandular epithelium or specific glandular epithelial secreted factors including LIF (Stewart et al., 1992; White et al., 2007; Filant and Spencer, 2013). The gene discussed is LIF; the disease is Infertility.