Pregnancy-associated microRNAs in plasma as potential molecular markers of ectopic pregnancy.

OBJECTIVE

To investigate cell-free pregnancy-associated microRNAs as molecular markers for the diagnosis of ectopic pregnancy.

DESIGN

Laboratory study using human plasma samples.

SETTING

Research unit in a university hospital.

PATIENT(S): Plasma samples from 18 women with ectopic pregnancies (EP group), 12 women with spontaneous abortion (SA group), and 26 normal women with singleton pregnancies (NP group).

INTERVENTION(S): Total RNAs containing small RNA molecules extracted from 1.2 mL of plasma.

MAIN OUTCOME MEASURE(S): Plasma concentrations of cell-free microRNAs measured by quantitative real-time reverse-transcriptase polymerase chain reaction.

RESULT(S): Plasma concentrations of cell-free pregnancy-associated microRNAs (miR-323-3p, miR-515-3p, miR-517a, miR-517c, and miR-518b) and serum concentration of human chorionic gonadotropin (hCG) were confirmed to have statistically significantly different plasma or serum concentrations in women with EP, SA, or NP. There was no statistically significant difference in the plasma concentrations of cell-free miR-21 between the three groups. By correlation coefficient analysis, no relationship was detected between serum hCG levels and plasma cell-free miR-517c, miR-515-3p, miR-517a, miR-518b, miR-323-3p, or miR-21 levels. Plasma concentrations of cell-free miR-517a could distinguish EP/SA from NP, yielding an area under the curve of 0.9654 (95% confidence interval, 0.9172-1.0). Plasma concentrations of cell-free miR-323-3p could distinguish EP from SA, yielding an area under the curve of 0.7454 (95% confidence interval, 0.5558-0.9349).

CONCLUSION(S): Cell-free pregnancy-associated microRNAs have potential as molecular markers of ectopic pregnancy.