The NHS Cumbria report found a strong link between lifestyles and unsuccessful pregnancies.
One in five mothers reviewed for the report had a body mass index (BMI) of more than 35, and a third of the mothers smoked during pregnancy.
In comparison, from the general maternity population, around one in ten mothers have a BMI of more than 35 and one in six smoke throughout their pregnancy.
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Kerrie brings you Sunday night's forecast
The highest risk of snow is from the NW later on Monday into Tuesday. For all it will remain cold with raw days and frosty, icy nights
Wintry start for some and windy. Brightening later