Comparative Analysis of Renal Biomarkers and Derived Uric Acid Ratios among Pregnant and Non-Pregnant Women in Port Harcourt, Nigeria

Abstract

Background: Pregnancy is associated with significant physiological changes in renal function, which influence the interpretation of biochemical markers. However, population-specific data on renal biomarkers and derived indices among pregnant women in sub-Saharan Africa remain limited. Objective: This study aimed to comparatively assess renal biomarkers, electrolyte profiles, and derived ratios among pregnant and non-pregnant women in Port Harcourt, Nigeria. Methods: A cross-sectional study was conducted involving 150 women, comprising 90 pregnant participants and 60 non-pregnant controls. Pregnant women were stratified equally across the three trimesters. Serum urea, creatinine, uric acid, and electrolytes (sodium, potassium, chloride, and bicarbonate) were analyzed using standard laboratory methods. Derived indices, including urea-to-creatinine and uric acid-to-creatinine ratios, were calculated. Statistical analysis was performed using SPSS version 24, with significance set at p < 0.05. Results: Pregnant women exhibited significantly higher levels of serum creatinine, urea, uric acid, potassium, chloride, and bicarbonate compared to non-pregnant controls (p < 0.05), while sodium levels showed no significant difference. The uric acid-to-creatinine ratio was significantly elevated, whereas the urea-to-creatinine ratio was significantly reduced among pregnant women. Serum creatinine increased significantly across trimesters, while other biomarkers remained relatively stable. Chloride levels decreased significantly in the third trimester. Conclusion: Pregnancy is associated with significant alterations in renal biomarkers and derived indices. These findings underscore the importance of population-specific reference ranges and support the clinical relevance of biomarker ratios in maternal health assessment and early detection of renal dysfunction.