Factors that predict low hematocrit levels in the postpartum patient after vaginal delivery

OBJECTIVE: The purpose of this study was to provide a viable alternative to routine postpartum hematocrit measurement, by a determination of the clinical risk factors that identify patients with anemia and an examination of the resulting cost savings. STUDY DESIGN: In this retrospective review, cases (postpartum hematocrit level, <26%; subgroup hematocrit level, <23%) and control subjects were culled from the records of all vaginal deliveries from February 1997 to July 1998. Charts were reviewed for demographic characteristics, medical history, nursing assessments, and postpartum hematocrit measurements. Logistic regression modeling determined the best set of risk factors for the identification of low postpartum hematocrit levels. RESULTS: From 1484 vaginal deliveries, 117 of the women (8%) had postpartum hematocrit levels of <26%. Estimated blood loss of >500 mL, Hispanic ethnicity, dizziness, or third- or fourth-degree laceration were the factors that identified 82.9% of the women with hematocrit levels of <26% and identified 97.4% of the women with hematocrit levels of <23%. Only 39.3% of the women would have required postpartum hematocrit measurement to obtain these detection rates. CONCLUSION: Four risk factors (estimated blood loss of >500 mL, Hispanic ethnicity, dizziness, and third- or fourth-degree laceration) can safely determine the necessity of a postpartum hematocrit measurement.