A one-time prescription for healthy eating and exercise probably won't help most women. "It needs to be an ongoing conversation that evolves over the course of the pregnancy," explained Patrick Catalano, MD. And interventions need to be adjusted along the way.

Calorie counts and energy expenditure are part of the issue, "but metabolic changes also take place during pregnancy that we don't know all that much about yet, and that may complicate interventions," Dr Catalano pointed out.

Recommendations on weight gain during pregnancy, issued by the Institute of Medicine, are an excellent starting point, Dr Catalano said. 

But, he added, physicians are not always the best professionals to help these women. Nutritionists, behaviourists, and exercise therapists are often in a better position to provide appropriate advice and counselling.

"My practice has a nutritionist and I wish we had a behaviourist," said Dr Catalano. "There are economic implications and, of course, even healthy eating can be expensive and therefore inaccessible to many."

- American Diabetes Association (ADA) 76th Scientific Sessions: Session 3-CT-SY04. Presented June 11, 2016.