Background: Recurrent Pregnancy loss is defined as the spontaneous end of a pregnancy before the age of fetal viability and encompasses all losses of conception until 20 24 weeks gestation. Guidelines from the European Society of Human Reproduction and Embryology (ESHRE) and the American Society for Reproductive Medicine (ASRM) define recurrent pregnancy loss as the failure of two or more clinically recognized pregnancies. MiRNAs are small non-coding RNAs, with an average 22 nucleotides in length. Most miRNAs are transcribed from DNA sequences into primary miRNAs (pri-miRNAs) and processed into precursor miRNAs (pre-miRNAs) and mature miRNAs. In most cases, miRNAs interact with the 3′UTR of target mRNAs to suppress gene expression. As well as their established and emerging roles in normal pregnancy, miRNAs through their ability to dynamically regulate gene expression are also believed to contribute to pregnancy-related pathologies including implantation failure and recurrent pregnancy loss, pre-eclampsia, preterm labor, as well as intrauterine growth restriction. It is well-recognized that consistent failure of endometrial receptivity for embryo implantation may have an immunological basis with altered immune cell and cytokine populations being observed in the endometrium of females with a history of recurrent pregnancy loss