Women who are pregnant carry a significantly higher chance of being involved in a serious car crash, according to a Canadian survey.
Those in the second trimester of their pregnancy reportedly see their risk rise by more than two-fifths (42%).
Among the group of more than 500,000 women quizzed for the study, an average of 177 crashes per month were recorded during the three-year period prior to pregnancy. But the rate became 252 per month in this middling pregnancy period.
Around one in 50 pregnant drivers will be involved in a serious accident, with the higher crash rate "explained almost completely" by multiple-vehicle crashes when the woman is driving.
The findings stress the necessity of more careful driving, said head researcher Dr Donald Redelmeier, from the University of Toronto.
Dr Redelmeier warned of irreparable consequences for mother and child in even minor accidents.
There were no similar accident increases noted among car passengers or pregnant pedestrians, and pregnancy did not raise the rate of falling over or risky behaviour.
The Canadian research, involving more than half a million pregnant women, has appeared in the Canadian Medical Association Journal.
Copyright Press Association 2014