London: Ladies, here`s another reason why you should shed the flab -- overweight pregnant women are more likely to be overdue and have more complicated births, a new study has claimed.
Researchers at Liverpool University found that women who were overweight or obese before they conceived were more likely to have a longer pregnancy, need to have labour induced artificially and to go on to require caesarean section births.
The study, published in the `British Journal of Obstetrics and Gynaecology`, examined the records of almost 30,000 women who gave birth over four years.
Three in 10 obese women were overdue, defined as still pregnant ten days after their due date, compared with around two in ten of healthy weight women. More than a third of obese women had their labour induced, compared with just over a quarter of normal weight women, the study found.
In addition, almost three in 10 obese women had an induction of labour which later resulted in a caesarean delivery compared to less than two in ten normal weight women.
However, more than seven in 10 obese women still gave birth naturally and the rates of complications in labour and for the baby were the same as in normal weight women, the study found.
Lead author Dr Sarah Arrowsmith said: "Maternal obesity has become one of the most commonly occurring risk factors in obstetric practice including greater risk of prolonged pregnancy.
"The importance of this research is that it investigates delivery outcomes for women who are obese with prolonged gestation and receiving labour induction.
"The fact that the majority of obese women did have a vaginal delivery, with labour complications being largely comparable to normal weight women, suggests that induction of labour in obese women with prolonged pregnancy is a safe method for managing these difficult pregnancies.
"Our findings were somewhat unexpected, given the well-reported complications surrounding obesity in pregnancy, but were clinically reassuring. Our current research is focused towards underlying causes of prolonged pregnancy, which can affect up to 10 per cent of women, as currently we know little about it."