In this work we aimed to identify the differentially expressed proteins and their potential roles during pen-implantation period through proteomics-based approach. Adult healthy female mice were mated naturally with fertile males to produce pregnancy. The models of pseudopregnancy, delayed implantation, and artificial decidualization were established. The protein profile between pre-implantation (D1) and implantation (D5) period was compared by two-dimensional electrophoresis (2-DE) and identified by mass spectrometry (MS). 2-DE yielded comparative images presenting over 500 protein spots in D1 and D5 mouse endometrium. 15 proteins were identified, of which stathmin 1, Apo-A1, hnRNP H3, transgelin 2 and arginase 1 were validated by western blotting. Stathmin 1 expression did not change in pseudopregnancy, but activation of implantation, or induction of decidualization increased it dramatically. Under non-pregnant status, progesterone alone or in combination with17 beta-estradiol increased it dramatically. Our results clarified the protein profile in mouse endometrium during implantation. The specific expression profile of stathmin 1 suggested that it should be involved in implantation and serve as a potential regulator of this process. These findings may contribute to the better understanding of the molecules events during embryo implantation, and subsequently improve the ability to treat infertility. (C) 2015 Elsevier Inc. All rights reserved.