Effect of motor vehicle crashes on adverse fetal outcomes.

Abstract

To assess the effect of maternal involvement in motor vehicle crashes on the likelihood of adverse pregnancy outcomes and to estimate the effect of seatbelt use in reducing the occurrence of those outcomes. Statewide motor vehicle crash, birth, and fetal death records from 1992 to 1999 were probabilistically linked. Logistic regression was used to compare the likelihood of adverse birth and fetal outcomes including low birth weight, prematurity, placental abruption, fetal distress, excessive bleeding, fetal death, and other complications among pregnant women in crashes and those not in crashes. Of 322,704 single live resident births, 8938 mothers (2.8%) experienced a crash during pregnancy. Pregnant women using seatbelts were not significantly more at risk for adverse fetal outcomes than pregnant women not in crashes. However, pregnant women who did not wear seatbelts during a crash were 1.3 times more likely to have a low birth weight infant than pregnant women not in a crash (95% confidence interval [CI] 1.0, 1.6) and twice as likely to experience excessive maternal bleeding than belted pregnant women in a crash (95% CI 1.0, 4.2). Forty-five of 2645 fetal deaths were linked to a motor vehicle crash, with unbelted pregnant women 2.8 times more likely to experience a fetal death than belted pregnant women in crashes (95% CI 1.4, 5.6). Pregnant women should be counseled to wear seatbelts throughout pregnancy and reduce crash risk.