Conclusions
Our study shows that overexpression of miR-93-5p, miR-15b-5p, and miR-191-5p in serum at early gestation is associated with spontaneous PTD in a general population. Further research is needed to evaluate the potential of these miRNAs as future biomarkers for spontaneous PTD, as well as their pathophysiological role in spontaneous PTD.
Material and methods
This study is a nested case-control study within the CERVIX study. The CERVIX study evaluated the ability of cervical length screening with transvaginal ultrasound to identify women at risk of PTD. In the present study, women who delivered spontaneously <34 weeks (n = 61) were compared with a control group of women who delivered at full term (39 + 0 to 40 + 6 gestational weeks, n = 205). Archived serum samples were analyzed with RT-qPCR for miRNA expression levels of let-7a-5p, miR-150-5p, miR-15b-5p, miR-185-5p, miR-191-5p, miR-19b-3p, miR-23a-3p, miR-374a-5p, and miR-93-5p. The mean relative expression was compared between the groups. Sub-analyses were performed for women delivering <32, <30, and <28 weeks vs the full-term group.
Methods
This study is a nested case-control study within the CERVIX study. The CERVIX study evaluated the ability of cervical length screening with transvaginal ultrasound to identify women at risk of PTD. In the present study, women who delivered spontaneously <34 weeks (n = 61) were compared with a control group of women who delivered at full term (39 + 0 to 40 + 6 gestational weeks, n = 205). Archived serum samples were analyzed with RT-qPCR for miRNA expression levels of let-7a-5p, miR-150-5p, miR-15b-5p, miR-185-5p, miR-191-5p, miR-19b-3p, miR-23a-3p, miR-374a-5p, and miR-93-5p. The mean relative expression was compared between the groups. Sub-analyses were performed for women delivering <32, <30, and <28 weeks vs the full-term group.
Results
The analyzed miRNAs were not significantly differentially expressed in women delivering <34 weeks compared to those delivering at full term. MiR-191-5p and miR-93-5p were significantly overexpressed in women who delivered <32 weeks, and further increase in fold change was observed with decreasing gestational age at delivery. The level of miR-15b-5p was significantly higher in women delivering at <30 weeks compared to those delivering at full term. Conclusions: Our study shows that overexpression of miR-93-5p, miR-15b-5p, and miR-191-5p in serum at early gestation is associated with spontaneous PTD in a general population. Further research is needed to evaluate the potential of these miRNAs as future biomarkers for spontaneous PTD, as well as their pathophysiological role in spontaneous PTD.