Risk factors for composite adverse outcomes of postpartum haemorrhage, Mpilo Central Hospital, Bulawayo, Zimbabwe

Background Globally, primary postpartum haemorrhage continues to cause considerable maternal morbidity and mortality. The aim of this study was to determine the risk factors for composite adverse outcomes of postpartum haemorrhage. The findings could potentially be used to anticipate and prevent composite adverse outcomes of postpartum haemorrhage. Methods This was a retrospective cross-sectional study carried out at Mpilo Central Hospital, a government tertiary referral centre, covering the period 1 July 2016 to 30 November 2019. Participants were included in the study if they had a diagnosis of postpartum haemorrhage. Those variables that had a p<0.2 from the univariate logistic regression analyses were considered for multivariable logistic regression. The association between independent variables and the dependent variable was assessed using odds ratio with 95% confidence intervals, to identify independent risk factors for composite adverse outcomes in PPH. A p< 0.05 was taken as statistically significant. Results The independent risk factors for composite adverse outcomes of postpartum haemorrhage were place of dwelling (AOR 4.57, 95% CI 1.87-11.12, p =0.01), prior Caesarean section (AOR 2.57, 95% CI 1.10-6.00, p =0.03), antepartum haemorrhage (AOR 5.45, 95% CI 2.23-13.27, p <0.0001), antenatal haemoglobin level (AOR 19.64, 95% CI 1.44-268.50, p =0.03), and current delivery by Caesarean section (AOR 10.21, 95% CI 4.39-23.74, p <0.0001).  Blood loss was also an independent risk factor for composite adverse outcomes of postpartum haemorrhage with the following blood loss; 1001-1500ml (AOR 9.94, 95% CI 3.68-26.88, p <0.0001), 500-1000ml (AOR 41.27, 95% CI 11.32-150.54, p <0.0001), and 2001ml (AOR 164.77, 95% CI 31.06-874.25, p<0.0001). Conclusion This study found that the independent predictors for composite adverse outcomes of PPH were rural dwelling, prior Caesarean section, antenatal haemoglobin level, current delivery by Caesarean section, and blood loss. In low- and middle-income countries such information could help in increasing clinical vigilance and policy making, and preventing maternal deaths.