Obesity is not only a risk factor for the development of gestational and type 2 diabetes, but also other serious complications of pregnancy. Weight gain during pregnancy is also associated with complications such as pre-eclampsia.
A meta-analysis of 44 randomised controlled trials involving more than 7000 women investigated the effects of diet, exercise or a combination on weight gain during pregnancy, and any adverse effects on mother and child. The research, published in the BMJ, found weight management interventions in pregnancy were effective in reducing weight gain in the mother.
The researchers, led by Dr Shakila Thangaratinam from Queen Mary, University of London, concluded that weight management interventions were safe and effective for overweight pregnant women. They found that dietary intervention resulted in the largest average reduction in weight gain (almost 4 kg) compared with just 0.7 kg for exercise and 1 kg for a combination of the two. Diet also offered the most benefit in preventing pregnancy complications such as pre-eclampsia, diabetes, high blood pressure and premature birth.
However, an accompanying BMJ editorial suggested the research does not provide the evidence needed for NICE to reassess the guidelines for weight management in pregnancy.
In a recent article in the Journal of DIabetes Nursing, Dr Julie Abayomi and Margaret Charnley called for clear guidelines for weight management and healthy eating interventions in pregnancy.
Overweight and obesity are increasing dramatically in pregnancy. A 2009 study in Liverpool by Dr Abayomi and colleagues found that 27% of women booking in for antenatal care were overweight (BMI 25–29.9 kg/m2) and 17% were obese (BMI >30 kg/m2). Morbid obesity in pregnancy is also becoming increasingly common; in the same study, 113 pregnant women had a BMI >39.9 kg/m2; the largest BMI recorded was 65.7 kg/m2.