Abstract
Objective: To determine the frequency of significant postpartum blood loss underdiagnosed by visual estimation by comparing clinical assessment with an objective laboratory criterion.
Materials and methods: A retrospective observational analytical study included women aged 16–35 years with singleton pregnancies who underwent vaginal or cesarean delivery at a hospital in Mazatlán, Mexico, between July 2023 and July 2024. Visual blood loss estimation was compared with a postpartum hemoglobin decrease ≥2 g/dl accompanied by a hematocrit reduction. Agreement between paired assessments was evaluated using McNemar’s exact test and Cohen’s kappa coefficient.
Results: Ninety-six women were included. Mean quantified blood loss was 791.15±736.46 ml. Visual estimation identified clinically significant bleeding in 33/96 women (34.4%), whereas the laboratory criterion identified 69/95 women (72.6%). Fifty were classified as negative by visual estimation but positive by laboratory assessment. McNemar’s exact test demonstrated significant discordance between methods (p=3.02 × 10⁻⁶). Visual estimation showed 27.5% sensitivity, 50.0% specificity, 59.4% positive predictive value, 20.6% negative predictive value, 33.7% accuracy, and poor agreement (κ = −0.156).
Conclusions: Visual estimation substantially underestimated postpartum blood loss and demonstrated poor agreement with laboratory findings. Standardized objective blood-loss assessment may improve early recognition and management of postpartum hemorrhage.
Cesar Alejandro Chávez-Jiménez, Francisco Javier Castro-Apodaca, Gloria María Peña-García, Dalia Magaña-Ordorica, Melina Rabelo-Aguilar, Rosa Ávila-Valdez, Roberto Joel Tirado-Reyes, José Héctor Carreón-Tiscareño, Adrián Canizalez-Román, Joel Murillo-Llanes, Aníbal Zaldívar-Colado, Nancy Godoy-Rodríguez, Talia Gierut, Debra Gierut
