Motor vehicle accident during the second or third trimester of pregnancy

To evaluate the need of immediate treatment, follow-up and consequences of different types of traffic accidents during pregnancy.

A retrospective analysis covering five years involving thirty-five pregnant women involved in motor vehicle accidents at 22-39 weeks of gestation.

Fifteen of the 35 women were involved in frontal impact collisions, and suffered mild subjective and objective symptoms; all their fetuses survived and were delivered at term. Fifteen other women were involved in broadside collisions; two of these were riding a bicycle. These 15 women had clear objective findings like uterine contractions or tenderness, and some of them needed tocolytic therapy and hospitalization up to eight days. This was significantly longer than in those involved in frontal impact collisions. However, the broadside accidents did not have any adverse effect on pregnancy outcomes either. Five women were involved in serious accidents at speeds of 80-110 km/h, and one mother and her fetus died immediately because of rupture of the uterus and the cervical joint and spinal canal. Four other fetuses were found dead on arrival at hospital or soon after. In all cases the cause of fetal loss was placental abruption. The presence of fetal blood cells in maternal blood was evaluated in 15 of 35 patients, but was positive in only one.

Frontal collisions are associated with lower vehicular speed, less trauma and no acute or later effects on pregnancy, whereas broadside collisions and high speed (> 80 km/h) cause more symptoms. The latter type of accidents are associated with high risk of placental abruption and of fetal and maternal death. Fortunately the symptoms are evident immediately after the accident, and early hospital discharge is possible if no abnormalities are present during the first hours.