Identifying the risk factors for carbetocin failure during caesarean section: a retrospective cohort study

Objective.To evaluate risk factors associated with carbetocin failure during caesarean section in a Malaysian tertiary hospital. Materials and Methods.We conducted a retrospective cohort study between 1 st of January and 30 th of June 2023, including all women who received carbetocin during caesarean section at a tertiary centre in Malaysia.Carbetocin failure was defined by a composite outcome: estimated blood loss ≥1000 mL, ≥10% drop in haematocrit, ≥4 g/dL drop in haemoglobin, need for additional uterotonics, or second-line interventions.Secondary outcomes included iron supplementation, blood transfusion, and prolonged hospital stay.Univariate and multivariate logistic regression analyses were performed to identify independent predictors of carbetocin failure, expressed as adjusted odds ratios (AOR) with 95% confidence intervals (CI).Results.A total of 447 women received carbetocin; 191 (42.7%) experienced carbetocin failure.Multivariate analysis identified preeclampsia (AOR 3.53, 95%CI 1.02-12.21,p = 0.047), previous postpartum haemorrhage (AOR 3.71, 95%CI: 0.80-17.28,p = 0.094), and higher foetal weight (AOR 1.000, 95%CI 1.000-1.001,p = 0.017) as significant risk factors.Obesity, age, parity, and pre-existing anaemia were not significantly associated with failure.Among those with carbetocin failure, 83.8% required additional uterotonics and 26.7% developed postpartum haemorrhage.Conclusions.Carbetocin failure following caesarean section was associated with preeclampsia, prior postpartum haemorrhage, and increased foetal weight.Obesity was not an independent predictor.These findings may support improved clinical risk stratification and highlight the need for further multicentre research.