📘 Postpartum Hemorrhage (PPH) (Important for OBG Nursing, GNM/BSc Nursing, NHM, AIIMS, NORCET, GPSC Staff Nurse Exams) ✅ 1. Introduction / Definition: Postpartum hemorrhage (PPH) is defined as blood loss of ≥500 mL after vaginal delivery or ≥1000 mL after cesarean section, within 24 hours (primary PPH) or after 24 hours up to 6 weeks postpartum (secondary PPH). It is a leading cause of maternal mortality, especially in developing countries.