The fact that it is defined as a type of diabetes that occurs during pregnancy means that its possible complications during pregnancy can be prevented, warded off, ameliorated, and, when necessary, treated.
The capacity for type-2 diabetes to insinuate itself into once-“normal” lives is, to use a mild word, noteworthy. As though there weren’t enough things to consider with pregnancy these days, there’s “gestational diabetes” to be aware of—and not develop, or to get prompt treatment for.
Defined at its most basic, gestational diabetes mellitis (GDM) is any onset of glucose intolerance first apparent or recognized during pregnancy. According to the American Diabetic Association assessment in 2003, in the U.S. GDM complicates 7% of pregnancies, with 200,000 cases reported annually.
In 2008, the Nation Institutes of Health reported that it affected 2% to 5% of pregnancies. The small discrepancy in rates does not necessarily reflect an increase or decline in incidence. The variables may well have to do with factors such as the quality of care a pregnant woman receives.
Which women are at least risk?
What characteristics indicate women at greater risk?
What causes GDM?
It’s not, or not only, the legendary “cravings” pregnant women feel for certain foods that causes GDM. That said, smart eating and regular checks of serum glucose and weight are front-line deterrents.
The U.S. Mayo Clinic puts it this way in its overview of the topic (verbatim):
“Any pregnancy complication is concerning, but there's good news. Expectant women can help control gestational diabetes by eating healthy foods, exercising and, if necessary, taking medication. Controlling blood sugar can prevent a difficult birth and keep you and your baby healthy.
“In gestational diabetes, blood sugar usually returns to normal soon after delivery. But if you've had gestational diabetes, you're at risk for type 2 diabetes. You'll continue working with your health care team to monitor and manage your blood sugar.”
With respect to causes, the Mayo Clinic could hardly be more plain: “Researchers don't know why some women develop gestational diabetes.”
Its explanation of the physiology, in the same article, is equally clear and in lay language we reproduce here verbatim:
“Your body digests the food you eat to produce sugar (glucose) that enters your bloodstream. In response, your pancreas—a large gland behind your stomach—produces insulin. Insulin is a hormone that helps glucose move from your bloodstream into your body's cells, where it's used as energy.
“During pregnancy, the placenta, which connects your baby to your blood supply, produces high levels of various other hormones. Almost all of them impair the action of insulin in your cells, raising your blood sugar. Modest elevation of blood sugar after meals is normal during pregnancy.
“As your baby grows, the placenta produces more and more insulin-counteracting hormones. In gestational diabetes, the placental hormones provoke a rise in blood sugar to a level that can affect the growth and welfare of your baby. Gestational diabetes usually develops during the last half of pregnancy—sometimes as early as the 20th week, but generally not until later.”
Again, the Mayo Clinic article is superb and clear here. In brief summary:
Complications for the mother could include:
Complications for the baby could include:
Specialists agree that blood sugar testing should begin at the first obstetrical appointment and remain a regular part of follow-up examinations and treatment. Some (but not all) mothers who develop GDM may need to have insulin injections during pregnancy. With or without a resort to insulin, any and all treatment should take place under the close supervision of an appropriate medical professional.
More detailed discussion of blood-sugar monitoring, relevant treatment, diet plans, and other pertinent matters can be found in the first three sites in our list of Sources/Readings, below.
Labor, birth, and post-natal considerations
UptoDate states unambiguously that blood-sugar levels will be monitored during labor—and that most women have normal blood-sugar levels during labor and do not require insulin injections. Also, while the presence of GDM does not mandate birth by caesarian section, there may be related reasons for that choice for delivery.
Post-birth, close monitoring of blood-glucose levels of both mother and infant(s) is strongly recommended, and on a regular basis.
Prevention, and amelioration during pregnancy
Unsurprisingly, the best preventive measures are eating properly, maintaining an appropriate weight, and doing regular exercise. But because each of us is an individual with a unique physiology, all those matters are best managed under the supervision of an appropriate, trained professional.
Exercise during pregnancy is strongly encouraged when appropriate. Most forms of exercise will require adaptations as the pregnancy lengthens, but there are helpful forms of exercise that can be practiced safely virtually up to delivery. As obviously, when pregnancy complications yield an order of bed rest, exercise should be radically modified and in many cases stopped. Breathing exercises remain possible.
The single most comprehensive and authoritative source:
The latest, with detailed information on issues from testing to diet: