I didn't drive at all for about six months after my son was born. As someone who was not a particularly confident driver to begin with, sleep deprivation made me utterly terrified of getting behind the wheel. I could hardly remember my own name so the thought of driving, and more specifically transporting my precious new cargo had me breaking out in a cold sweat.
While walking everywhere or using public transport wasn't always convenient, a new study confirms that my instincts were spot on.
According to the research, published in the journal Sleep, drivers who slept fewer than seven hours in the previous 24 had higher odds of being involved in - and responsible for - car crashes.The greatest risk however, was for drivers who slept fewer than four hours.
While the study didn't focus on new parents, its findings are relevant to exhausted mums and dads struggling to catch enough Zs. Research commissioned by sleep technology brand Simba earlier this year found that new parents only manage four hours and 44 minutes of sleep per night during their baby's first year, placing them firmly in the danger zone for accidents.
As part of the study, researchers analysed data from the US Department of Transportation, which included 5,470 crashes. The team found that drivers who clocked fewer than four hours had 15.1 times the odds of being responsible for car crashes, compared with those who got the recommended seven to nine hours in the 24 hour period prior. Those who slept fewer than four hours had a particularly high risk of being involved in a single-vehicle car crash, which are more likely to result in injury or death.
"Being awake isn't the same as being alert. Falling asleep isn't the only risk," said lead author Brian Tefft. "Even if they manage to stay awake, sleep-deprived drivers are still at increased risk of making mistakes - like failing to notice something important, or misjudging a gap in traffic - which can have tragic consequences."
But while the study consisted of a broad sample of individuals, findings published in 2016 in the Journal of Maternal Child Health were more specific. In a group of new mothers and fathers, 22 per cent reported at least one near miss accident, while approximately six per cent reported a crash.
"Poor sleep is common in new parents and we provide preliminary evidence that sleep disruption in this population is associated with near miss motor vehicle accidents," the authors wrote at the time. "Drowsy driving results in thousands of unnecessary serious injuries and fatalities each year; raising public awareness that new parents are a high-risk group is important."
in Australia, fatigue is one of the top three contributors to the road toll. In addition, fatigue-related accidents are twice as likely to be fatal as sleeping drivers can't brake.
Not sure if you're too sleepy to drive? You can test your tired self here as part of this NSW road safety campaign.