Risks of motor vehicle crash before and during pregnancy: A population-based controlled study in Taiwan

Changes in risk of motor vehicle crashes (MVCs) during pregnancy are less known, and very few studies have assessed this issue by using unselected population-based datasets and adopting a before-and-during design. The study aimed to address the risk of MVC events in association with pregnancy using a national pregnant women cohort in Taiwan.

We conducted a self-matched design in which each woman served as a driver before and during pregnancy. A total of 1,372,664 pregnant women with live birth(s) at 18-50 years of age between 2008 and 2017 were identified from the Birth Notification dataset. MVC events as a driver were ascertained from the Police-reported Traffic Accident Registry dataset. We calculated the rate ratio (RR) with a 95 % confidence interval (CI) using the conditional Poisson regression model to compare the MVC event rates between pre-pregnancy and pregnancy periods.

The overall rate of MVC events was significantly reduced during pregnancy (RR = 0.69, 95 % confidence interval (CI) = 0.68-0.71). Mothers with alcoholism during pregnancy were associated with an increased RR at 2.00 but with a very wide CI. Reduction in RR was primarily attributed to the reduced MVC event rate involving scooter crashes (0.60, 95 % CI = 0.58-0.62).

Although MVC event rates decreased during women became pregnant, many women drivers were still involved in MVCs during pregnancy. Their potential maternal and perinatal conditions along with their offspring's health outcomes need further investigations.