Seat belts work for everyone, including pregnant women. Like all occupants, they are more likely to be seriously injured if they do not wear seat belts.

A pregnant woman should wear a lap-shoulder belt, and the lap portion should be worn as low as possible, below the rounding, throughout the pregnancy.
The best way to protect the fetus is to protect the mother. When a seat belt is worn properly, it is more likely that the fetus will not be hurt in a crash. For pregnant women, as for anyone, the key to making seat belts effective is wearing them properly.
Lap-Shoulder Belt
Seat Belt ExtenderTransmission Component and System Description Automatic Transmission Unit
The mechanical components of the 6T70/75 are as follows:A torque converter with an electronically controlled capacity clutch-(ECCC)Off axis chain driven vane-type fluid pump assemblyInput sun gear and carrier assembly4–5–6 and 3–5 reverse clutch assembly with turbine shaftLow and reverse clutc ...