Levels of miR-21and miR-182 in Unexplained Recurrent Spontaneous Abortion

Abstract

MicroRNAs are small non-coding RNAs involved in regulating gene expression. Recurrent spontaneous abortion (RSA) is defined as two or more consecutive pregnancy losses before 20 weeks of gestation. The aim of this study was to explore the expression level of three pregnancy-associated miRNAs in maternal plasma in normal pregnancy and RSA cases. We conducted a case control study on a 100 Palestinian women: 60 patients with at least two unexplained consecutive pregnancy losses (half of them were in first trimester pregnant and the other half were non-pregnant) and 40 healthy controls with at least two live births and no history of pregnancy loss (half of them were in first trimester of pregnancy and the other half were non-pregnant). We investigated the relative expression of miR-21, miR-155 and miR-182 using quantitative real-time polymerase chain reaction and Ct method experiments. Differential expression was evaluated using Student t-test and fold change analyses. The expression difference of miR-21 and miR-182 between patients and controls in the pregnant subjects showed statistically significant difference (p-value ≤ 0.05) with fold decrease of 1.5 and 5.6, respectively. In the non-pregnant women miR-21 expression was also significantly different with fold decrease of 2.4. In conclusion, miR-21 could be a novel marker for idiopathic RSA as its level was significantly lower in patients before being pregnant and during pregnancy.