RESUMO
Background: The objective of this study was to compare the Fetal Zone Depth (FZD) of fetal adrenal gland in term and preterm labor cases. Methods: Twenty nine preterm pregnant women at 29-36 weeks of gestation with single pregnancy admitted with the clinical diagnosis of preterm labor and the comparison group of 33 pregnant women at 37-40 weeks with term pregnancy were included in this study. FZD and Total Gland Depth (TGD) of fetal adrenal gland of the entire fetuses in sagittal plane were ultrasonographically measured and FZD/TGD ratios were calculated. Demographic and clinical features, laboratory findings and fetal adrenal gland FZD/TGD ratios were compared between the two groups. Results: No difference was found between the two groups in respect of age, number of pregnancies and delivery method (P >0.05); yet preterm birth history and duration of hospital stay were higher in preterm group (P <0.05). Fetal adrenal gland FZD/TGD ratio was statistically significantly higher in preterm group compared to the term group (55.4% ± 4.9 vs. 47.7% ± 5.6; P <0.001). Conclusion: The growth in FZ as a fetal adaptation mechanism in increased fetal stress in preterm labor cases was at a significant level. Once supported by more comprehensive studies, we think that this result would be beneficial in the prediction of preterm labor in clinical practice.