Abstract

Background: Postpartum hemorrhage (PPH) remains a leading cause of maternal morbidity and mortality, particularly in low-resource settings. Uterine atony is the most common etiology, marked by inadequate uterine contraction following delivery. Emerging evidence suggests a role for inflammatory cytokines, including interleukin-6 (IL-6) and interleukin-1 beta (IL-1β), in regulating uterine contractility and vascular remodelling. Aim: This study aimed to evaluate maternal plasma levels of IL-6 and IL-1β in women with PPH due to uterine atony compared to controls, to assess their potential as predictive biomarkers and explore their clinical utility in risk stratification. Materials and Methods: A case-control study was conducted involving 88 pregnant women—44 with PPH secondary to uterine atony and 44 matched controls without PPH. Blood samples were collected antepartum and within 24 hours postpartum, and cytokine levels were measured using enzyme-linked immunosorbent assay (ELISA). Demographic, obstetric, hematologic, and clinical management data were recorded. Statistical analyses included t-tests, chi-square tests, and receiver operating characteristic (ROC) curve analysis. Results: IL-6 levels were significantly higher in cases than controls (45.58 ± 29.83 vs. 13.83 ± 5.86 pg/mL; p < 0.0001), as were IL-1β levels (25.01 ± 15.44 vs. 8.39 ± 4.02 pg/mL; p = 0.01). IL-6 showed superior diagnostic accuracy (AUC = 0.812), with 100% sensitivity and 70% specificity for severe PPH. Elevated cytokines were associated with greater blood loss, increased transfusion needs, adverse maternal outcomes, longer hospital stays, and higher rates of surgical intervention. Conclusion:IL-6 is a promising biomarker for predicting PPH severity and identifying high-risk patients early. Its incorporation into postpartum risk assessment protocols could enhance maternal care. Further multicenter studies are warranted to validate these findings and explore targeted anti-inflammatory therapies.

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