Pathare ADS, et al. - Given that DNA methylation profile in mid-secretory phase of endometrium differs from other phases in natural menstrual cycle, therefore, researchers conducted whole-genome methylation and gene expression profiling in endometrium of recurrent implantation failure patients (RIF) during IVF under controlled ovarian stimulation, to examine the impairment in endometrial receptivity. Overall 448 CpG sites were identified through differential methylation in RIF patients. A significant negative correlation of methylation in NLRP2 gene in inflammatory pathway with gene expression was observed, whereas hypomethylation of SERPINA5 gene (already known to be implicated in endometrial receptivity) in promoter region with highest delta beta value as well as its upregulation in gene expression analysis was revealed. Findings revealed the prevalence of aberrant methylation of genes implicated in immunological functions and G protein activation, this might be indicative of a role in endometrial receptivity. However, further confirmation of findings on a larger cohort of IVF-RIF patients is required.