Figures show that as women delay having children and go into pregnancy weighing more, gestational diabetes becomes increasingly common.
Although the disease usually goes away after delivery, it can have permanent consequences. Not only can the mother be prone to develop diabetes later in life, but their babies are also at greater risk for chronic health problems.
The babies are likely to be born larger and be bigger as children. Their predisposition to childhood obesity begins in the womb - contributing to an intractable problem in Tennessee, where about one in five children is obese, the sixth-highest rate in the nation. One study showed that children of mothers with gestational diabetes were about twice as likely to be obese at age 11 as the children of non-diabetic mothers. These babies also are more susceptible to birth defects and at greater risk for attention deficit hyperactivity disorder and autism.
Early diagnosis and treatment are crucial for changing those odds, doctors say. Some even recommend that women planning to start families get screened for pre-diabetes before pregnancy. Well-intended comments and nourishing gifts from friends and families cause difficulties for many expectant moms, who are told they’re eating for two and wind up consuming twice as much food.
The U.S. Centers for Disease Control and Prevention (CDC) estimates gestational diabetes affects between 2 percent and 10 percent of pregnancies. Doctors in Middle Tennessee believe prevalence here is at the higher end. “It is definitely on the increase,” said Dr. Cathy Deppen, an OB-GYN at Summit Medical Center, who has practiced in the region for 14 years.
As many as half of those diagnosed with gestational diabetes will in their later years develop diabetes as a permanent condition. Dr. Megan McCauley, an endocrinologist at Summit, said overeating during pregnancy often becomes a way of life. “I see a number of patients who have developed Type 2 diabetes a year, two years, five years down the line,” McCauley said. “They are eating the same way (they were) when they were pregnant. It’s one of those things where the cravings kicked in and because they indulged in them, they were never willing to give them up.”
“The hormones that your placenta makes while you’re pregnant affect your glucose metabolism,” Deppen said. “For some of us, that tips the scale.” Weight is a primary factor. Over the past decade, the prevalence of women who were overweight or obese before pregnancy has increased from 46.9 percent to 52.9 percent, according to the CDC. Simultaneously, the percentage of women who were underweight before pregnancy decreased from 6.2 percent to 4.5 percent.
Three years ago, the Institute of Medicine changed its recommended-weight-gain guidelines for pregnant women for the first time in nearly 20 years. The guidelines, which are expected to come into effect within three months, will lower the threshold of what is deemed safe blood-glucose levels in pregnant women and experts are predicting a substantial rise in cases of gestational diabetes.
The threshold for diagnosis is being lowered because an international study (The Hyperglycemia And Adverse Pregnancy Outcomes study) found a baby’s health can be at risk when maternal blood-glucose levels are lower than the levels currently classified as gestational diabetes. So the latest guidelines will see women diagnosed if they have a fasting blood-glucose level of 5.1mmol/L or more – the level was previously 5.5mmol/L. Levels will still be measured via tests done at 24 to 28 weeks, when this type of diabetes usually develops.
The official gestational diabetes rate has stood at about five per cent for some time, according to the Australian Diabetes in Pregnancy Society (ADIPS), although recent Australian research suggests the true number is closer to eight or nine per cent, or one in 12 women. The change to guidelines means that in some parts of Australia, 12 to 13 per cent of pregnant women, or one in eight, will now be found to have gestational diabetes.
Shelly Branch, a diabetes nurse educator for Baptist Hospital and Middle Tennessee Medical Center, said pregnant women should have regular exercise, but family members often discourage this. “I’m not asking them to be a marathon runner but to get up and walk 20 to 30 minutes every day,” she said. In most cases, the expectant mother needs only about 300 extra calories a day. Branch said, “That little person inside you is not another adult inside you. It’s a peanut trying to get there.”
Women are at greater risk if they have a family history of type-2 diabetes, if they are over 30, if they are overweight, if they are an indigenous Australian or Torres Strait Islander, if they are from a Vietnamese, Chinese, Middle Eastern, Polynesian or Melanesian background, or if they have had gestational diabetes during previous pregnancies.