Procedures
Inclusion took place in the immediate postpartum period from April 27,
2017, to April 2, 2019. The volume of bleeding was quantified for
vaginal deliveries by using a graduated/marked collection bag and for
caesarean deliveries, by aspiration and weighing the blood loss. PPH
prevention and management followed the French clinical practice
guidelines.11
The exposed group comprised the women who had had a primary PPH (≥500 mL
in the 24 hours after delivery) and the unexposed group, which did not.
For each woman with PPH, we planned to recruit 2 women without it: the
ones immediately before and after the delivery of the woman with
PPH.14 The investigator provided women with a written
information sheet and obtained their written consent before their
discharge.14
The study was registered at ClinicalTrials.gov (NCT 03120208).