The Comparison Between Fetal Renal Length and Sacral Length in Determining Gestational Age

Objective: The purpose of this research was to compare the relationship between fetal renal length, sacral length, and gestational age (GA), in a cohort of second- and third-trimester pregnancies. Materials and Methods: Fetal renal and sacral length were measured on pregnant volunteers between 18 and 37 weeks gestation. Both parameters were then compared to GA using a Pearson correlation statistic. Results: Based on the Pearson test results, fetal renal length ( r = .772; p = .0001) was statistically significant and had a strongly positive association with GA. Likewise, the fetal sacral length ( r = .752; p = .0001) was statistically significant and had a strongly positive association with GA. Conclusion: This study demonstrated that fetal renal length may be slightly stronger in association, as diagnostic parameter, to determine GA. Certainly fetal sacral length also was a highly associated diagnostic for determining GA. Future research may identify if these diagnostic parameters should be considered, as part of obstetric biometry, especially if routine fetal measurements could not be obtained.