Significant bleeding in the first 24 hours after delivery is called primary postpartum hemorrhage, and after that it's called secondary, or late, postpartum hemorrhage.

分娩后24小时以内的大量出血被定义为原发性产后出血，而发生在分娩24小时后的大量出血则被称为继发性（迟发型）产后出血。