In an automobile accident, the pregnant woman's thorax and pelvis are both restrained by the belt, but her abdomen is free to move in the direction determined by the impact. Because the fetus is floating free inside her, the most common injury is that the placenta becomes partially or completely detached, which means that the baby cannot get enough oxygen. More rarely the baby sustains physical injury due to impacts with the mother's pelvic bones, the car's interior, or an airbag.

Unfortunately little about fetuses in car accidents. To shed more light on this area,in 2000, Volvo developed the world's first official computer model of a pregnant crash dummy named Linda. Volvo says that It is difficult and perhaps even impossible to build a physical model with as much detail and accuracy in human tissue response as they have in Linda and say that if a physical model were to be made, with realistic tissue responses, it would likely be destroyed after a single crash. Their computer model can endure as many crashes as they like ? and at any severity level. Computer modeling works well when there is enough knowledge to assure that the model will behave accurately in all circumstances. When there isn't enough knowledge, testing is done with the real thing, or in this case a pregnant crash dummy who can show researchers just how the complex human body is likely to move when it is thrown about in an automobile accident.

These days, the automobile airbag systems are under scrutiny, and the National Highway Traffic Safety Administration has adopted new rules for airbags that require testing and certification with high risk drivers and passengers including pregnant women.As automobile manufactures search for a safer airbag solution, Since, along with children, and small adults, a pregnant woman is considered to be among the special risk groups for airbag injury, pregnant crash dummies are playing a vital role in the new airbag research. An apparatus for simulating a pregnant female human during a crash test includes a torso having an abdominal cavity which contains a fetal insert.The body of the crash dummy fetus resides in a special container in which it can move in response to pressure, or sudden accelleration. The crash dummy baby accurately simulates a human fetus with a head portion connected to a chest portion. Load cell accelerometers mounted in the fetal dummy chest and head detect acceleration of the fetal body.

Initially, research with pregnant crash dummies focused on seat belt safety. Findings weren't good. Seat belts keep the mom from sailing out of the car, but don't protect the fetus,who is likely to suffer from a detached placenta. Airbags, which have been shown to maim and kill both drivers and passengers are even worse for a pregnant woman. The government recommends being no closer than 10 inches from the airbag, and private researchers recommend 12 inches. In late pregnancy, a woman may find it difficult to scoot a seat far enough back to achieve that. For now, the government recommends that people who are at risk of injury from airbags, which includes pregnant women, apply for permission to have an airbag switch installed.