Trauma during pregnancy: a population-based analysis of maternal outcome.

Background: Serious injury during pregnancy is known to cause adverse maternal outcomes. However, the significance of minor injuries in adverse maternal outcomes requires clarification because most injuries sustained during pregnancy are minor ones.

Methods: Two population-based databases (inpatient and ambulatory care) were used to identify pregnant women who had severe (required hospitalization) or minor injuries (required ambulatory care only) prenatally. ICD-9-CM coding was used to categorize the types of prenatal injury and complications during delivery. The patient demographics, types and timing of the injuries, and their association with adverse maternal outcomes were compared among the uninjured, those with minor injury, and those with severe injury. Odds ratios were calculated to estimate the risks of having adverse outcomes in injured pregnant women compared with those who are uninjured.

Results: The severely injured women tended to be younger (<20 years old), lived in less urbanized regions, and had lower income levels than those who were uninjured or had minor injury. Motor vehicle crash was the most common mechanism of injury. While minor injuries were associated with preterm labor [odds ratio (OR)=1.25], a severe injury was strongly associated with increased risks of preterm labor, placental abruption, uterine rupture, and maternal death, especially during the third trimester (OR=2.71, 6.12, 7.79, and 20.15, respectively). Injuries away from the trunk could also lead to adverse maternal outcomes.

Conclusions: Trauma during pregnancy, whether minor or severe, is associated with unfavorable maternal outcomes. Injuries considered minor for the general population are not minor for pregnant women. Therefore, these patients should be monitored carefully.