Pregnant women should watch their diets, because eating for two could increase the risk of complications, warn researchers.
They found that mothers who minimised weight gain through a healthy, calorie-controlled diet were less likely to suffer life-threatening pre-eclampsia.
Researchers from Queen Mary, University of London, said helping women with “weight management methods” had no ill-effects on their babies and prevented complications including diabetes, high blood pressure and premature birth.
Controlled diets reduced weight gain during pregnancy by 3kg, on average, when compared with women who were not given advice.
Their study, published on bmj.com, also claimed that eating for two during pregnancy could leave women saddled with the extra kilos for life.
Doctors have warned that babies born to overweight women are at greater risk in later life of diabetes and obesity themselves.
Consultant obstetrician Dr Shakila Thangaratinam, who led the study, said: “We are seeing more and more women who gain excess weight when they are pregnant. These women and their babies are at increased risk of complications. Weight control is difficult, but this study shows that by carefully advising women on weight management methods, especially diet, we can reduce weight gain during pregnancy.
“It also shows that following a controlled diet has the potential to reduce the risk of a number of pregnancy complications.
“Women may be concerned that dieting during pregnancy could have a negative impact on their babies. This research is reassuring because it showed dieting is safe and the baby’s weight isn’t affected.”
About a third of women gain more than the recommended amount of weight during pregnancy.
Thangaratinam said that many failed to shed this weight before embarking on another pregnancy.
“They have their second child without managing to lose the weight left from the previous pregnancy, and some women never manage to shift it,” she said.
The research assessed the results of 44 separate studies using data on more than 7 000 women to investigate the effect of diet, exercise, or a combination of the two on the mother’s weight and risk of problems for mother or child.
In some of the studies, expectant women were restricted to 1 800 to 2 400 calories a day – the recommended intake for an average woman who is not pregnant is 2 000 calories a day.
The analysis showed that pregnant women who followed a diet were 33 percent less likely to develop pre-eclampsia, which raises blood pressure and can lead to strokes and even death.
Their risk of gestational diabetes was 60 percent lower, their risk of gestational high blood pressure was 70 percent lower and the risk of premature birth was 32 percent lower.
There have been fears that dieting might lead to a drop in babies’ birthweights, but according to the study it was unaffected.
Jane Brewin, of pregnancy research charity Tommy’s, said: “There is growing evidence to re-evaluate current guidelines for weight management during pregnancy.” – Daily Mail