A prospective controlled study of outcome after trauma during pregnancy.

In a prospective cohort study, 85 women who suffered varying degrees of trauma during pregnancy (12 to 41 weeks) were compared with a control group of pregnant women matched for gestational age. Fetomaternal transfusion occurred significantly more frequently in the study group (30.6% vs 8.2%, p less than 0.05). Study subjects whose placentas were anteriorly placed were at increased risk for fetomaternal transfusion on comparison with other placental positions (47% vs 23.5%, p less than 0.05). Immediate adverse outcomes including abruptio placentae occurred frequently in the study group (9.4%) and were not predictable on the basis of injury severity. When immediate adverse outcomes were excluded, there was no difference in pregnancy outcome. Four hours of cardiotocographic monitoring used as a screening tool was found to be an extremely sensitive but nonspecific indicator of immediate adverse outcomes. On the basis of these findings, it is recommended that routine screening for fetomaternal transfusion occur in all pregnant women who suffer trauma during pregnancy beyond 11 weeks' gestation and that a minimum of 4 hours of cardiotocographic monitoring occur in women greater than 20 weeks' gestation.