Wearing a seat belt can be uncomfortable for pregnant women. As a result, they may tuck the belt behind them or under an arm. Fear of an exploding air bag during an accident makes it tempting to turn off the air bag as well.
Neither is a good idea, experts say.
All pregnant women should wear seat belts and wear them properly, according to Dr. Robert Atlas, chair of the department of obstetrics at Mercy Hospital in Baltimore. "Many pregnant women die each year because of car accidents,” he says.
Seat belts not optional
About 300 to 1,000 unborn babies die each year in car accidents; the exact number is not known since states are not required to report fetal deaths. Seat belts prevent about 11,900 deaths and 325,000 injuries each year, according to the National Highway Transportation Safety Administration (NHTSA).
According to the National Safety Council, people who buckle up are 50 percent more likely to survive a serious car crash and avoid injuries.
In addition, it's the law. Every state except New Hampshire has a mandatory seat belt law, according to the Insurance Institute for Highway Safety (IIHS). Driving without a seat belt may result in a fine ranging from $10 (several states, including Arizona and Idaho) to $200 (Texas).
Best way to buckle up
For the safety of both mother and child, seat belts always should be worn and the air bag always should be on; some vehicles offer the option of turning the air bag off. The seat belt and air bag are designed to work together in the event of a crash.
The most important part of protecting the fetus is keeping the mother alive, says Stefan Duma, professor and head of the Virginia Tech-Wake Forest University School of Biomedical Engineering and Sciences. "If mom dies, then the baby almost always dies. To this end, the combination of the air bag and seat belt is the best protection for the mom," Duma says.
Both lap and shoulder belts should be worn, with the lap belt buckled low on the hip bones (below the belly) and the shoulder belt should be across the center of the chest and off to the side of the belly, says Dr. Sara Morelli, an OB/GYN at University Reproductive Associates in New Jersey.
The seat should be as far away from the dashboard as possible, but you still should be able to easily reach the foot pedals; the steering wheel should be tilted upward, away from the belly, Morelli says.
NHTSA recommends keeping at least 10 inches between the center of your chest and the steering wheel cover or dashboard. Adjust your seat to maintain this 10-inch minimum as your pregnancy progresses.
"If a pregnant woman is involved in an accident, even a minor one, she should see a health care provider right away, in case she needs monitoring," Morelli says.
In an uncomplicated pregnancy, there's no particular time when pregnant women are advised to stop driving, but circumstances may vary and should be discussed with a woman's health care provider, Morelli says. If high blood pressure or pre-term labor is a concern, you want to think about not driving at all, Atlas says.
Road trip precautions
Pregnant women driving on long trips should take additional precautions.
The American Congress of Obstetricians and Gynecologists recommends that pregnant women drive no more than five to six hours a day.
Morelli says being pregnant (in addition to long periods of immobility) is a risk factor for deep vein thrombosis, a blood clot formation in the veins of the legs or other parts of the body that can travel to a lung and be fatal. "A pregnant woman on a long car trip should make frequent stops to walk around and stretch her legs," she says.
Car safety research
New advancements in vehicle safety include research with "pregnant" crash test dummies. Ford worked with the School of Biomedical Engineering and Sciences to develop a computer-aided model of a pregnant woman for crash test simulations.
Computerized human models show the effects of crash forces on skeletal structures, soft tissues and internal organs -- something a traditional crash test dummy can’t do.
Ford also wanted its engineers (both men and non-pregnant women) to understand the comfort needs and potential restrictions of pregnant women. The "empathy belly" includes a strap that the engineers put on their chests to produce shortness of breath and a water belly or lead weights, which put pressure on the belly and gives the wearer the appearance of being pregnant -- 33 pounds heavier and nine months' pregnant.