The effects of uterine ligaments on fetal injury risk in frontal automobile crashes

A finite element model of a seven-month pregnant uterus was created and integrated into a multibody human model. The pregnant occupant model was validated using known abdominal response corridors. Tests of occupants with no restraint, a three-point belt and a three-point belt plus airbag at 35 km/h were simulated to evaluate the effects of four support ligaments connected to the uterus. The primary injury predictor, the peak uterine strain on the anterior uterus, was not found to change appreciably by the absence of the support ligaments; however, high local stress concentrations were found at the ligament attachment sites. Based on these results, it is recommended that computational models of the pregnant occupant contain the supporting ligaments since the stress concentrations may result in increased injury risk in other test configurations or loading conditions.