Obese and overweight women are at greater risk of preterm birth than women of normal weight, Canadian researchers have found.
They reviewed 84 studies involving more than one million women. They found the heavier the woman, the higher the risk of induced preterm birth before 37 weeks.
Very obese women had a 70 per cent higher risk than normal weight women. Overweight and obese women also had a higher risk of early preterm births, with babies being born before 32 or 33 weeks.
The authors said overweight and obese expectant mothers should be offered counselling to warn them of the risks.