Detection of MMP-9 and TIMP-3 mRNA expression in the villi of patients undergoing early spontaneous abortion: A report of 30 cases.

The aim of the present study was to investigate the correlation of matrix metalloproteinase (MMP)-9 and tissue inhibitor of matrix metalloproteinase inhibitor (TIMP)-3 expression with spontaneous abortion (SA) during early pregnancy. The villus tissues of 30 SA cases and 20 requested abortion cases were collected during surgery and constituted the SA and normal abortion (NA) groups, respectively. The total villous RNA was extracted and the expression levels of MMP -9 and TIMP-3 mRNA were detected by reverse transcription-polymerase chain reaction (RT-PCR) assay to calculate the MMP-9/TIMP-3 mRNA ratio. The MMP-9 mRNA expression level and MMP-9/TIMP-3 mRNA ratio of the SA group were significantly higher than those of the NA group (P<0.01), while the TIMP-3 mRNA levels of the two groups were similar (P>0.05). The MMP-9 mRNA expression level of the SA group was higher than that of the NA group; thus, the MMP-9/TIMP-3 mRNA ratio was higher. These results suggest that the expression level of MMP-9 mRNA and the MMP-9/TIMP-3 mRNA ratio are associated with SA.