Uterine receptivity is disrupted in Rac1d/d uterus. (a, b) Relative expression levels of epithelial genes (a) and stromal genes (b) in Rac1f/f and Rac1d/d D4 uteri. Unpaired t test, *P<0.05. (c–e) In situ hybridization and immunostaining of epithelial and stromal marker genes in Rac1f/f and Rac1d/d D4 uteri. (f) Expression of ERα and PR receptors in Rac1f/f and Rac1d/d D4 uteri. (g) Ki67 staining in Rac1f/f and Rac1d/d uteri at D4 morning (0800 h) and evening (2000 h). le, luminal epithelium; ge, glandular epithelium; s, stroma; myo, myometrium. Scale bars, 100 μm