Identifying women most likely to benefit from prevention strategies for postpartum hemorrhage

Objective: To identify women who are most likely to benefit from primary prevention strategies for postpartum hemorrhage (PPH). Study Design: In a retrospective patient cohort, we applied recursive partitioning algorithms to identify the most discriminant risk factors and their interactions, and calculated the ‘number needed to treat’ to prevent a single case of PPH (estimated blood loss >1000 ml). Result: By delivery category, the highest risk groups with ‘number needed to treat’ ranging from 4 to 7 were: (1) vaginal delivery (PPH=0.7% of 16 218)—macrosomia with gestational diabetes and manual removal of the placenta; (2) primary cesarean (PPH=18.7% of 2696)—macrosomia and multiparity; and (3) repeat cesarean (PPH=16.0% of 1832)—uterine incision other than low transverse and failed vaginal birth after cesarean. Conclusion: Clinical profiles that identify women at risk for PPH can provide a foundation for the development of primary prevention strategies.