Seat belts, particularly those in older cars, are not as effective at protecting women, as they are men, from being injured in a car accident. A recent study by the American Journal of Public Health determined that because seat belts were designed for the average person, that women, who are generally smaller than men, are more likely to be injured from airbags and the seat-belts themselves.
One of the reasons for the seat belt size issues is due to the fact that men are much more likely to be in a car accident involving serious personal injuries. Consequently, car manufacturers, relying on the law of averages, build their safety equipment to protect those most likely to be in a deadly accident. Unfortunately, this leaves women more vulnerable when they have an accident.
Thankfully, newer cars have sensors which adjust the safety mechanisms for whomever is driving the car. We hope these technological advances will protect all vehicle occupants.