WASHINGTON — A change in testing could nearly triple the number of women diagnosed with diabetes during pregnancy, but would catching milder cases help mother or baby? A government panel is urging more research to find that out before doctors make the switch.
Gestational diabetes — the kind that strikes during pregnancy — is a growing problem. More women are getting it as they wait until their 30s or later to have a baby, and as they increasingly begin their pregnancies already overweight.
This is one of the most common complications of pregnancy, and just about every woman gets checked for it. That’s because if a mother’s high blood sugar isn’t controlled, the fetus can grow too large, leading to C-sections and early deliveries.
There are other problems, too: Mom can get dangerous high blood pressure; the baby can be born with low blood sugar; the baby’s risk of obesity in childhood is increased. And while this kind of diabetes usually disappears when the baby’s born, the mother is left with another risk. Months or years later, half of women who had it wind up developing full-fledged Type 2 diabetes.
Doctors today diagnose gestational diabetes in about 5 percent to 6 percent of US pregnancies, or about 240,000 a year, according to specialists convened this week by the National Institutes of Health.
Most US doctors use a two-step testing method. But now there is a push for doctors to switch to a simpler one-step test that is used in other parts of the world.
The one-step approach, backed by the American Diabetes Association and World Health Organization, isn’t just about the convenience of getting diagnosed in one doctor visit or two. It also would lower the blood sugar threshold for diagnosing the condition.
‘‘The implications of this are very, very large, and there are so many unanswered questions,’’ said Dr. Catherine Spong of the National Institute of Child Health and Human Development.
On Wednesday, the NIH-appointed panel agreed, and said many more pregnant women would be classified with gestational diabetes — 15 to 20 percent — if doctors widely adopted the one-step approach.
The more aggressive approach treats milder cases with diet and exercise, not medication. But that’s still a lot of women who would get extra medical care, such as nutritionist visits and doctor checks of their blood sugar and their baby’s growth, not to mention uncertainty about whether C-sections would increase.
But there has been no study of whether treating cases milder than are diagnosed today makes any difference to the health of mother and baby, the specialists concluded.
Under the two-step method, nearly every woman drinks a super-sweet liquid, and has a blood test an hour later to see how the body processes the sugar.
Those who fail repeat the test with a larger drink and three hours of blood tests.