By Thomas R. Collins

NEW ORLEANS — Women found to have gestational diabetes are good candidates for diabetes prevention programs and intervening during the post-partum period is an important way to try to improve the prospects of future pregnancies, an expert on the issue told an audience here.

Young adults do not use health care services consistently, but more than 80 percent of women will deliver a child at some point during their lives and will therefore be screened for gestational diabetes, said Lucinda England, MD MSPH, of the Division of Reproductive Health at the U.S. Centers for Disease Control and Prevention, at the 69th Scientific Sessions of the American Diabetes Association.

“From a public health perspective, using pregnancy as an opportunity to identify women at high risk for chronic diseases is really ideal,” Dr. England said.

Studies have concluded that from 13 percent to 19 percent of diabetes cases in women in the United States would have been preceded by a pregnancy involving gestational diabetes, according to a 2003 pooled analysis (Cheung and Byth Diabetes Care 2003), demonstrating the powerful predictive ability of gestational diabetes. Type 2 diabetes before a pregnancy increases the chance of complications during the pregnancy, Dr. England said.

Standard guidelines are clear that women with gestational diabetes should be coached about the importance of weight loss and exercise and that those with impaired fasting glucose and impaired glucose tolerance should get medical nutritional therapy.

Out of 4 million births a year, there are about 200,000 pregnancies involving gestational diabetes, or 5 percent. Of those, 10,000 of the women or 5 percent, develop diabetes; 30,000, or 15 percent, develop pre-diabetes; and 160,000, or 80 percent, are normal.

There is evidence that diabetes can be prevented or delayed in women with a history of gestational diabetes.
In a diabetes prevention program trial, investigators found a 50 percent reduction in diabetes risk among women with a history of gestational diabetes, when they were treated with either lifestyle or metformin therapy, compared to women who were unaffected by gestational diabetes.

The study (Ratner et al. J Clin Endocrin Metab 2008) found that only five to six women with impaired glucose tolerance and a history of gestational diabetes had to be treated over three years to prevent one case of diabetes. That compared to having to treat nine to 24 women with only IGT but no gestational diabetes history to prevent one case.

Dr. England noted that it might not be a simple matter to have intervention programs translate from paper into actual practice. The women involved in the Ratner study were age 43, on average — older than most women in their child-bearing years and the average time since their GDM-affected pregnancy was 12 years.

A study using birth certificate data of women in the general population who had gestational diabetes while pregnant found that half of them were under 30 years old, a third were unmarried and a large percentage were on government medical assistance programs, so their benefits were likely to run out after the birth, Dr. England said.

“Women with recent GDM-affected pregnancy are likely to be very different from women in randomized trials,” she said.
Plus, women report many barriers to weight control, from time constraints to fatigue to neighborhood safety concerns.
Dr. England said there are still several gaps in the research, including comparing the benefits of intervention in young women to older women and the need for randomized controlled trials of weight management programs for post-partum women with recent gestational diabetes.

“There are still several unanswered questions,” she said.