KLF12 and endometriosis: Mariee et al. (2012) reported decreased LIF expression in RIF patients. MiR-181a is a member of the miR-181 family whose expression is suppressed by estrogen. MiR-181a also inhibits the expression of KLF12, which is required for endometrial receptivity. It has been reported that KLF12 expression is increased in the endometrium of RIF and endometriosis patients (Maillot et al., 2009; Zhang et al., 2015).