No abstract

Early pregnancy loss (EPL), also termed early miscarriage, is determined as the unintentional expulsion of an embryo or fetus prior to the 12th week of gestation. EPL frequency is ~15% in pregnancies. Fetal development and growth is associate with placental function and vessel development; therefore, the placental genome would represent a useful miscarriage model for (epi)genetic and genomic studies. An important factor of placental development and function is epigenetic regulation of gene expression. microRNAs (miRNAs) are the primary epigenetic regulators which have an important role in placental development and function. In the present study, maternal plasma and villous tissue were collected from 16 EPL cases in 6th-8th gestational weeks (GWs) and 8 abortions (control group) in 6th-8th GWs. Detection of the differences in miRNA expression was performed using microarrays and dysregulated miRNAs were validated by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). miRNA microarray findings revealed that four miRNAs, including hsa-miRNA (miR)-125a-3p, hsa-miR-3663-3p, hsa-miR-423-5p and hsa-miR-575 were upregulated in tissue samples. In maternal plasma, two miRNAs (hsa-let-7c, hsa-miR-122) were upregulated and one miRNA (hsa-miR-135a) was downregulated. A total of 6 out of 7 dysregulated miRNAs were validated using RT-qPCR. The target genes of these dysregulated miRNAs were detected using the GeneSpring database. The aim of the present study was to detect dysregulated miRNAs in maternal plasma and villous cells and identify the target genes of dysregulated miRNAs and their associated pathways. The target gene analyses have revealed that the affected genes are primarily associated with cell migration, proliferation, implantation, adhesion, angiogenesis and differentiation and all are involved with EPL pathogenesis. Therefore, the present study may contribute to the understanding of the molecular mechanisms which lead to EPL.

Preeclampsia continues to be a mortal disease of pregnant women throughout the world. Recently, geneticists, allied with obstetricians, have opened new frontiers. MicroRNAs (miRNAs) are members of a class of small, noncoding RNA molecules. They are critical posttranscriptional regulators of gene expression. We extracted circulating miRNA from maternal plasma and quantified mir-152 and mir-210. We found up-regulated miR-210 levels as well as down-regulated mir-152 levels in preeclampsia patients.We propose that detection of increased mir-210 levels in maternal serum could be used to improve prediction methods for noninvasive prenatal diagnosis of preeclampsia.

We believe that the increased number of apoptosis in the placenta of pregnancies complicated with IUGR may have an important compensatory role to transmit nutrition and gas exchange easily to the fetus.

Abnormal amniotic fluid volume can be associated with increased maternal risk as well as perinatal morbidity and mortality. Polyhydramnios is often indicative of fetal, placental or maternal problems. In a large proportion of patients the aetiology of the disorder is unclear. Here we report on a case in which numerous fetal erythroblasts and large quantities of extracellular fetal DNA were found in the peripheral blood of a pregnant woman with idiopathic polyhydramnios bearing a male fetus. Following enrichment of erythroblasts by magnetic separation (MACS) and anti‐CD71 antibodies, approximately 45‐fold more erythroblasts were determined per ml peripheral maternal blood than in matched controls (231 versus 5). Single cell multiplex polymerase chain reaction (PCR) of individually micromanipulated erythroblasts showed that approximately 122 of these were of fetal origin. The concentration of extracellular fetal circulatory DNA in maternal plasma was determined by real‐time quantitative PCR and shown to be almost double that of the control group (749.2 versus 404 fetal genome equivalents per ml maternal plasma). It can be speculated that the increased intrauterine pressure in polyhydramnios leads to an enhanced influx of fetal cells and free extracellular fetal DNA into the maternal circulation. This hypothesis will have to be tested with further cases. Copyright © 2000 John Wiley & Sons, Ltd.