Pregnant women are at special risk of morbidity and mortality when in a motor vehicle accident. Some do not wear seat belts because of the discomfort on their abdomen when wearing a seat belt. Others do not wear their seat belts appropriately, across the pelvic region, and suffer from injury to their abdomen as well as to their developing fetus.
Even when wearing the seat belt properly, the forces of the accident can cause trauma to the uterus which is essentially a big ball attached at the lower end with ligaments. The uterus can tear and there can be injury to the fetus who is basically freely floating in the uterus.
Trauma is believed to be the most common cause of non-obstetric death in pregnant women in the United States. Besides motor vehicle crashes, pregnant women are subject to domestic violence and severe falls from great heights.
Even with no external signs of injury to the uterus, the forces involved in trauma in a pregnant woman can lead to placental abruption. Placental abruption involves a separation of the placenta from the inside of the uterine wall, leading to serious bleeding, lack of oxygenation of the fetus, uterine contractions and possible fetal and maternal death due to hemorrhaging.
It is for this reason that all pregnant women involved in a traumatic injury should be evaluated for the possibility of an abruption. They should be evaluated with a blood pressure reading, uterine contraction monitoring, fetal monitoring and probable ultrasound of the uterus to check on the status of the placenta and fetus.
The women should otherwise be evaluated the same way as non-pregnant women with the exception that the uterus be placed offset to the major vessels. This is accomplished by placing a pillow beneath the right side of the woman to tilt her off the major vessels or to have the woman lie on her left side during the evaluation. The uterus, if on the major vessels, can disrupt the flow of blood through the abdominal aorta and vena cava, making increased pressure above the level of the disruption.
After the woman is stabilized from a cardiorespiratory status, electronic fetal monitoring should be done, which assesses the fetal heart rate and can tell if there are contractions going on. Severe or frequent contractions should be considered to be a sign of an abruption and surgical intervention in terms of an emergency cesarean section should be done in order to save the mother and child’s lives.
Electronic fetal monitoring is considered to be the most accurate way of determining fetal health after a trauma, in part because, if the fetus is showing a reactive pattern with a normal heart rate, the chances of a severe abruption is nearly impossible.
An ultrasound should follow a half hour period of fetal monitoring. Ultrasound can assess fetal movements, a sign of fetal health, as well as the status of the placenta, both its size and its attachment to the uterus.
The trick to maternal-fetal health is to learn how to properly apply a seat belt when riding in a motor vehicle and to seek medical attention as soon as an injury occurs.