Unfortunately, pregnant women are not excluded from being involved in traffic accidents. In most cases, the pregnant woman is the driver of the vehicle, which puts her at greater risk of injury due to the airbag or to the steering wheel.
A recent study looked at the need for immediate triage, treatment and follow up of pregnant women after several different types of traffic accidents. The study looked at five years of traffic accidents involving pregnant women which involved 35 women who were involved in a traffic accident at between 22 to 39 weeks of gestation. Of the total, fifteen of the women were involved in front end impact collisions. All of these women had mild symptoms after the accident but all the infants survived and were delivered at the normal time.
Fifteen other women were broadsided as a part of their traffic accident. Two were riding a bicycle and got injured in a bicycle-automobile collision. Of the women involved in a broadside collision, most had clear objective findings and some needed tocolytics in order to stop contractions. Some of these women needed hospitalization for up to eight days. It appears that broadside impacts are much more severe to pregnant women than head on collisions. Even so, most did not have an adverse impact on the outcome of the pregnancy and these women had healthy babies as well.
It turns out that five women were involved in serious accidents with speeds of 80-110 km/hr. One mother and fetus died immediately due to rupture of the uterus. One had a cervical joint and spinal canal injury. Four other fetuses died before they reached the hospital or died shortly after that. These babies died of placental abruption. There were fetal blood cells mixed with maternal cells in one case, while it was tested for in 15 cases.
The researchers concluded that front end traffic accidents are associated with less trauma than broadside collisions and high speed collisions. In most cases, the fetuses survived to term. Those infants that died, died from uterine rupture or placental abruption. Pregnant women need to be evaluated in the hospital for at least a day in order to make sure they don’t need tocolytics to stop contractions. A longer hospital stay may be necessary, depending on non-pregnancy related injuries or prolonged contractions.
As mentioned, the main cause of fetal demise was placental abruption in these traffic accidents. This happens when the placenta separates from the uterus due to trauma or spontaneous reasons. The loss of connection of the placenta from the uterus means that there is excessive bleeding inside the uterus, severe uterine contractions and a lack of oxygen to the fetus, who dies as a result. Fetuses can be saved if they are near term and if the abruption is only partial. An immediate cesarean section is required to save the fetus.
Rupture of the uterus can also happen. The uterine wall is really thin during pregnancy and a force on the uterus can rupture it, spilling the contents of the uterus into the abdominal cavity and causing excessive bleeding that can kill both mom and fetus.