Comparison of maternal serum calcidiol and microRNA-1323 expression in term and early preterm births.

Abstract

Objective Preterm birth remains a leading cause of neonatal morbidity and mortality. Maternal vitamin D status and epigenetic regulation may contribute to its pathogenesis. This study aimed to analyze differences in subject characteristics, calcidiol [25(OH)D] levels, and maternal blood microRNA-1323 (miRNA-1323) expression between term and early preterm (28-34 weeks) deliveries. Materials and Methods An analytical observational study with a comparative cross-sectional design was conducted among 80 parturient women, including 40 term (37-42 weeks) and 40 early preterm deliveries. Calcidiol levels were measured using enzyme-linked immunosorbent assay, and miRNA-1323 expression was analyzed by quantitative reverse transcription polymerase chain reaction with the ΔCq method. Statistical analyses included normality, non-parametric, and correlation tests (p<0.05). Results Mean maternal calcidiol levels were significantly higher in the early preterm group than in the term group (27.49±9.18 vs. 23.34±9.64 ng/mL; p=0.022), although both remained below the normal range. Median miRNA-1323 expression was also higher in the early preterm group, but not statistically significant (p=0.709). No significant correlation was observed between maternal calcidiol levels and miRNA-1323 expression in either group, indicating that these biomarkers were not directly associated in the present study and supporting further investigation into their individual contributions to early preterm birth. Conclusion Maternal calcidiol levels differed significantly between term and early preterm deliveries, whereas miRNA-1323 showed a non-significant increasing trend. Both biomarkers may reflect biological changes associated with preterm birth.