CLINICAL QUESTION

How sensitive and specific are tests used to diagnose postpartum hemorrhage in the first 24 hours after vaginal birth?

EVIDENCE-BASED ANSWER

Visual estimation of blood loss is not very sensitive (22%–48%) but is very specific (97%–99%) when used to diagnose postpartum hemorrhage in patients who deliver vaginally in a hospital setting. In contrast, using a calibrated drape plus observations (eg, heart rate, blood pressure, uterine tone, blood flow) to measure blood loss has good sensitivity (93%) and specificity (95%) for detecting postpartum hemorrhage, which is defined as blood loss of 500 mL or more for primary postpartum hemorrhage.¹ (Strength of Recommendation: A, consistent, good-quality, patient-oriented evidence.)

PRACTICE POINTERS

Postpartum hemorrhage is defined by the American College of Obstetricians and Gynecologists as a cumulative blood loss of 1,000 mL or more or blood loss accompanied by signs or symptoms of hypovolemia within 24 hours after birth.²

According to the World Health Organization (WHO), maternal death is defined as the annual number of deaths from any cause (excluding accidental or incidental causes) of female patients during pregnancy or within 42 days of being pregnant that is related to or aggravated by pregnancy or the management of pregnancy.³ Postpartum hemorrhage remains the leading preventable cause of maternal illness and death worldwide.