Objective The objective of this study was to evaluate whether trimester-specific D-dimer levels or the modified Wells score (MWS) is a useful risk stratification tool to exclude pregnant women at low risk of pulmonary embolism (PE) from diagnostic imaging. Study Design This is a prospective and retrospective cohort study. Pregnant women who underwent diagnostic imaging for suspected PE were prospectively enrolled. D-dimer serum levels were drawn, and a MWS was assigned. Pregnant women diagnosed with a PE before study launch who underwent diagnostic imaging and had a D-dimer level drawn were also evaluated. Results In this study, 17 patients were diagnosed with a PE and 42 patients had no PE on diagnostic imaging. Sixteen out of 17 patients with a PE versus 11 out of 42 without PE had an abnormal D-dimer level (p = 0.001). Four patients with a PE versus zero without a PE had an abnormal MWS (p = 0.005). The combination of a trimester-specific D-dimer level along with the MWS was abnormal in all 17 patients with a documented PE versus 11/42 (26.2%) patients without a documented PE (p = 0.001). Conclusion A combination of trimester-specific D-dimer levels along with a MWS can be used in pregnancy to triage women into a low-risk category for PE and thereby avoid radiation exposure in a majority of pregnant patients.

INTRODUCTION: Postpartum hemorrhage (PPH) is a leading cause of maternal mortality. A previous study (Dilla et al) showed statistically different hemorrhage rates among groups rated low, medium, and high risk, but each group had low overall hemorrhage rates. METHODS: From 9/2012-5/2013, women who delivered at Advocate Lutheran General Hospital at gestational age greater than 20 weeks were included in this retrospective case control study. Risk factors present on admission and during labor were given score of 1, 2, or 3 based on existing literature and recommendation by an expert panel. Each patient was labeled low, moderate, or high risk based on total score at time of delivery. Definition of PPH was considered estimated blood loss greater or equal to 500 cc for vaginal delivery, greater or equal to 1000 cc for cesarean section, or if uterotonic medications beyond standard Pitocin protocol were administered. RESULTS: Of 1227 women, 115 (9.37%) experienced a PPH. The incidence of PPH in each risk group was: low (7%), moderate (22%), and high (31%). The proportion of the total hemorrhages occurring in each group was: low (64%), moderate (32%), and high (3%). CONCLUSION: This predictive model was better at predicting PPH than previous studies. Future studies with larger patient populations are needed to validate these findings. This type of model using a summation of all risk factors prior to delivery may represent an improved way to predict and thus prevent PPH.