About one in 50 pregnant women will be involved in a serious motor-vehicle accident, typically during their second trimester, a new study reports.
"Pregnant women often ask me about the safety of air travel, scuba diving and hot tubs, yet many of them overlook traffic crashes, which are a greater threat during pregnancy," said study author Dr. Donald Redelmeier, a physician in the University of Toronto Department of Medicine and a researcher at the Institute for Clinical Evaluative Sciences (ICES).
In the study, researchers examined more than 500,000 pregnant women in Ontario before, during and after pregnancy. Each woman was followed for five years, including four years before delivery and one year after delivery. The researchers looked at whether typical conditions of pregnancy — nausea, fatigue, insomnia and distraction — were contributing to driver error and an increased risk of being in a traffic crashes that sent them to the hospital.
During the period before pregnancy, the study participants were involved in 6,922 crashes (an overall average of 177 per month). In contrast, women who were driving during their second trimester of pregnancy were involved in 727 traffic accidents (252 per month), which represents a 42 percent increase in risk over the baseline.
The researchers did not see similar increases among accidents in which women who were pedestrians or passengers, nor increases in the number of falls or risky behavior. [11 Big Fat Pregnancy Myths]
The study appears in today's (May 12) issue of the Canadian Medical Association Journal.
The reason for the link is not completely clear, but Redelmeier speculated that during the second trimester, women may develop a false sense of security that is often compounded by insomnia, back pain and a more hectic life in general. "They've made it through the risk of the first trimester, their minds are preoccupied with the birth of their child and they're rushing around trying to get things done before the big day," he said. "It's easy for them to get distracted."
These findings, Redelmeier said, emphasize the need for pregnant women to consider safe driving as part of their prenatal care. "There's no need to hire a driver or get someone else to drive," he said. "Just be more vigilant when you're driving. Use your seat belt, signal turns, reduce speed and minimize distractions. This is actually good advice for anyone."
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