Embryo implantation involves a complex sequence of events, and a large amount of molecules have been postulated to be involved in the interaction of embryo and endometrium. This study evaluated the endometrial expression of -inhibin and -glycan in the mid-secretory phase of women scheduled to in vitro fertilization (IVF) and tested whether these markers are associated with implantation failure. We performed a nested case-control study including 52 women submitted to IVF and embryo transfer, divided into 2 groups: cases with implantation failure (n = 33) and controls with confirmed clinical pregnancy (n = 19). Endometrial -inhibin and -glycan gene expression was evaluated in the mid-secretory phase of the natural menstrual cycle immediately before IVF, using real-time polymerase chain reaction. We found a higher gene expression of -inhibin (fold increase = 2.14 +/- 0.32, P < .05) and -glycan (fold increase = 1.44 +/- 0.16, P < .05) in implantation failure patients compared to confirmed clinical pregnancy patients. The areas under the receiver operating characteristics curves for prediction of implantation failure in this context were 0.692 and 0.678 for -inhibin and -glycan, respectively. The present results suggest that high expression levels of -inhibin and -glycan transcripts in secretory phase endometrium are associated with a lower chance of achieving pregnancy with IVF.