Wednesday August 29, 2007 (Foodconsumer.org) -- Higher maternal sugar levels caused by gestational diabetes increase risk of childhood obesity, but a good control of sugar levels during pregnancy can reduce the risk, according to a Kaiser Permanente study published in the September issue of Diabetes Care.
The study found a higher risk of childhood obesity in those who were born to the women who had a higher blood sugar level during pregnancy and that untreated gestational diabetes almost doubled a child's risk of obesity by age 5 to 7.
On the other hand, the study also found children whose mothers with gestational diabetes were treated during pregnancy had the same risk of becoming obese as others whose mothers had normal levels of blood sugar.
"This suggests that the 'metabolic imprinting' for childhood obesity that results from gestational diabetes in pregnant women may be reversible," said Teresa Hillier, MD, MS, lead author of the study, an endocrinologist and senior investigator at Kaiser Permanente's Center for Health Research (CHR) Northwest and Hawaii.
For the study, Hillier and colleagues at CHR in Portland and Hawaii analyzed medical records of 9,439 mother-child pairs in Oregon, Washington and Hawaii and the births were given between 1995 and 2000.
The women in the study were screened during pregnancy for the blood sugar level. Their children were measured for weight between 5 and 7. The association between maternal blood sugar and childhood obesity was analyzed.
Women who had high levels of blood sugar during pregnancy, but were untreated were 89 more likely to have overweight children and 82 percent more likely to have obese children by 5 to 7 years of age compared to those who had normal blood sugar.
Gestational diabetes, a condition that occurs during pregnancy and affects up to 8 percent of pregnant women each year in the United States, triggers insulin resistance and raises the women's blood sugar level.
Obesity and overweight affect nearly 7 million children in the country. It remains unknown how many cases of childhood obesity result from their mothers' gestational diabetes.
"Hyperglycemia during pregnancy is clearly playing a role in America's epidemic of childhood obesity," said Hillier.
"The key finding here is that the risk of overweight and obese children rises in step with higher levels of blood sugar during pregnancy. The good news for pregnant women is that by treating gestational diabetes, your children's risk of becoming overweight or obese drops considerably."
"My advice to pregnant women is three-fold: Discuss gestational diabetes screening with your doctor, usually between weeks 24 and 28 of pregnancy; if you have gestational diabetes, work with your physician to treat it, and stick with the treatment during your pregnancy. It's the best thing you can do to reduce your child's risk of obesity," said Dr. Hillier.
The message of the study is clear. Pregnant women who had high levels of blood sugar during pregnancy may want to consider treatment. But the treatment does not have to involve any medication.
Shimron-Nachmias L, Frishman S, and Hod M. from Rabin Medical Center, Beilinson Campus in Petach Tikva, Israel published an article in the October 2006 issue of Harefuah giving advice on dietary management of diabetic pregnancy.
They said there are two types of diabetes during pregnancy that need medical attention. Gestational diabetes mellitus (GDM), the main type of diabetes in pregnancy, usually appears in the second half of pregnancy and mainly affects fetal growth rate and can slow systemic development. Most women with this type of diabetes are treated with nutritional management only, according to the authors.
If diabetes exists before pregnancy, its effects begin at fertilization and implantation and continue throughout the pregnancy. This type of diabetes may cause early abortion, severe congenital defects and disrupted organogenesis. The condition is often treated with insulin. But the authors said nutrition management is still important in normalization of glucose levels.
To control blood sugar levels, Shimron-Nachmias and colleagues suggested that pregnant women use small meals, but frequently. The meals should contain carbohydrates that are not highly processed, rich in slowly digested starches and non-soluble polysaccharides. In a word, use a diet that releases glucose slowly so the body will be able to metabolize it in a timely fashion.
Two other problems should be avoided while controlling the blood sugar triggered by diabetes, according to Shimron-Nachmias and colleagues. They are ketosis, which can occur in the liver transforming fat into fatty acids and keto bodies and hypoglycemia, a condition that the glucose sugar level becomes too low, which can occur in women who are treated with insulin.