Factors Influencing Pregnant Women's Injuries and Fetal Loss Due to Motor Vehicle Collisions: A National Crash Data-Based Study.

To examine the factors that influence substantial injuries for pregnant women and negative fetal outcomes in motor vehicle collisions (MVCs), a retrospective analysis using the National Automotive Sampling System/Crashworthiness Data System was performed in Shiga University of Medical Science. We analyzed data from 736 pregnant women who, between 2001 and 2015, had injuries that were an abbreviated injury scale (AIS) score of one or more. The mean age was 25.9 ± 6.4 years and the mean gestational age was 26.2 ± 8.2 weeks. Additionally, 568 pregnant women had mild injuries and 168 had moderate to severe injuries. Logistic regression analysis revealed that seatbelt use (odds ratio (OR), 0.30), airbag deployment (OR, 2.00), and changes in velocity (21-40 km/h: OR, 3.03; 41-60 km/h: OR, 13.47; ≥61 km/h: OR, 44.56) were identified as independent predictors of having a moderate to severe injury. The positive and negative outcome groups included 231 and 12 pregnant women, respectively. Injury severity in pregnant women was identified as an independent predictor of a negative outcome (OR, 2.79). Avoiding moderate to severe maternal injuries is a high priority for saving the fetus, and education on appropriate seatbelt use and limiting vehicle speed for pregnant women is required.

Hit-and-runs more common with pedestrians lying on the road: Analysis of a nationwide database in Japan.

PURPOSE: To determine the trends with fatally or otherwise injured pedestrians lying on the road and the relationship to hit-and-run incidents in Japan. METHODS: We extracted data for 2012-2016 from the records of the Institute for Traffic Accident Research and Data Analysis, Japan, a nationwide traffic accident database. All the injured and fatally injured pedestrians were selected. We examined the levels of pedestrian injury, vehicle speed immediately before the collision, whether or not the pedestrian was lying on the road, and hit-and-run incidents. Chi-square test was employed to make a statistical comparison between the two groups. RESULTS: The database contained data on 286,383 pedestrian casualties and 7256 fatalities; 8.3% of fatalities (602 persons) and 0.6% of casualties (1827 persons) involved pedestrians lying on the road. The rates of fatalities and severe injuries were significantly higher for pedestrians who were lying on the road than for those who were not. Hit-and-run incidents were evident in 4.0% of casualties and 7.3% of fatalities. The rate of hit-and-run cases was also significantly higher among pedestrians who were lying on the road. Among fatally injured pedestrians not lying on the road, the rates with speeds of ≥30 km/h did not differ significantly between hit-and-run and other cases. However, when the pedestrians were lying on the road, the rate was significantly increased in hit-and-run cases. CONCLUSION: This is the first report to focus on pedestrians lying on the road and being involved in hit-and-run incidents. In addition to preventing hit-and-run incidents, prevention of pedestrians lying on the road could also decrease fatalities.

Mechanisms of Negative Fetal Outcome in Frontal Vehicle Colli-Sions Involving Unbelted Pregnant Drivers.

To determine the cause of negative fetal outcomes and the causative mechanism in a frontal collision, we analyzed the kinematics and mechanisms of injuries using an unbelted pregnant dummy, the Maternal Anthropometric Measurement Apparatus dummy, version 2B. Sled tests were performed to recreate frontal impact situations with impact speeds of 13, 26, and 40 km/h. Overall kinematics of the dummy were examined through high-speed video imaging. Quantitative dummy responses-such as time courses of the abdominal pressure, chest deflection, neck injury criteria (Nij), and displacement of the pelvis during impact-were also measured. The maximum abdominal pressure of 103.3 kPa was obtained at an impact speed of 13 km/h. The maximum chest deflection of 38.5 mm and Nij of 0.36 were obtained at an impact speed of 26 km/h. The highest maximum chest deflection of >40.9 mm, Nij of 0.61, and forward pelvis displacement of 478 mm were obtained at an impact speed of 40 km/h. Although the kinematics and mechanism of injuries of the dummy were different for different collision speeds, we found that unbelted pregnant drivers suffer severe or fatal injuries to the fetus even in low-speed collisions.