The potential for routinely weighing/measuring blood loss following vaginal birth to improve ascertainment: a retrospective study at two Victorian hospitals

Background: Determination of the volume of primary postpartum blood loss (i.e., within the first 24 hours following birth) is commonly estimated visually. This simple method is subject to intra‐ and inter‐operator error and variation, with the main concern being underestimation of blood loss. Safer Care Victoria (Australia) introduced a good practice point in 2019 of weighing/measuring blood and items following birth.

Methods: A retrospective analysis of routinely collected maternity data at two co‐governed Victorian maternity services (Hospitals A/B) compared documented blood loss when predominantly estimated visually (2016‐18) with weighing/measuring (2020‐22).

Results: Increased rates of reported blood loss ≥500mL following vaginal birth were noted across the two epochs, particularly for 500 to <1000mL at Hospital B (14.5% 2016‐18 to 20.1% 2020‐22, p<0.001) and 1000 to <1500mL (Hospital A: 5.2% to 6.2%, p=0.005; B: 4.7% to 5.9%, p<0.001). The threshold for consistently weighing/measuring blood loss rather than relying on visual estimation 70% of the time was higher for Hospital A (at ≥400mL) than for Hospital B (<100mL) by 2022.

Comment: Further research may consider staff factors, such as exposure to promotion of the practice of measuring blood loss; recency of their appointment to birth suite; availability of resources for measuring blood loss; birth suite culture; and relevant hospital policies.