Predictors of Postpartum Hemorrhage among Women Delivering Vaginally at Public Hospitals in Lusaka, Zambia

Primary postpartum hemorrhage (PPH) remains a major contributor to maternal morbidity and mortality in resource-limited settings. In this case-control study of 318 women delivering vaginally at public hospitals in Lusaka, Zambia, prolonged third stage of labor and specific intrapartum complications were independently associated with primary PPH. Duration of the third stage of labor was associated with increased odds of PPH (adjusted odds ratio [aOR] 1.1, 95% CI 1.05 - 1.46, P = 0.048). Uterine atony (aOR 7.4, 95% CI 4.5 - 14.6, P < 0.0001) and cervical tears (aOR 11.3, 95% CI 7.9 - 21.7, P < 0.0001) were strongly associated with PPH. Retained placenta was also an independent predictor (aOR 4.3, 95% CI 3.4 - 9.7, P = 0.001). Socio-demographic factors showed no meaningful association with PPH after multivariable adjustment. Secondary outcomes observed among cases included hemorrhagic shock, hysterectomy, ICU admission, and maternal death. These results emphasize early recognition and prevention of modifiable intrapartum risk factors to reduce PPH-related morbidity and mortality.