Gestational diabetes is a form of diabetes that begins or is first recognized during pregnancy, usually toward the end of the second trimester. Women with this form of diabetes are characterized by having elevated blood sugars, either fasting or after meals, and decreased tolerance to simple sugars in their diet. These women and their infants are at increased risk (perhaps as great as 1 in 5) of developing potentially serious problems during pregnancy and parturition (birth), such as premature labor and delivery, large infants, infant respiratory distress, infant hypoglycemia, stillbirth, and even maternal death, if nothing is done to treat their diabetes. However, good control of gestational diabetes eliminates essentially all of these problems. There are a number of factors that contribute to the development of gestational diabetes, such as genetic factors, weight gain and hormones produced by the placenta. Usually, because the placenta is delivered at birth and the hormones it produces are no longer present, gestational diabetes resolves after parturition. However, all women with gestational diabetes have a somewhat higher risk of developing diabetes later in life ( the exact risk is somewhere between 25 and 40%), even if it resolves after the birth of their baby. For this reason postpartum weight loss, maintenance of a desirable weight, regular exercise and continuing attention to optimal eating habits are encouraged and may help to prevent diabetes later on in life.



Normal blood sugars typically run between 60 and 100 in the fasting state and may go as high as 140 to 160 after meals. For a woman who is pregnant, a normal blood sugar is typically between 50 and 100 in the fasting state and as high as 120 to 130 after meals. When we treat women with gestational diabetes, we like to keep their blood sugars equal to or less than 120 all the time, and around 100 or less most of the time.



The first step in treating gestational diabetes is a careful dietary program supervised if possible by a registered dietician. By dividing up one's intake into frequent multiple smaller meals and snacks, one distributes the calories throughout the day and this helps to minimize the swings that occur in blood sugar levels after meals. A standard diet for a woman with gestational diabetes is three meals plus three snacks per day which is tightly controlled for carbohydrate intake.  Simple sugars that are rapidly absorbed into the bloodstream usually must be avoided. The goal of dietary therapy is to allow appropriate weight gain during pregnancy yet maintain the blood sugar in an acceptable range. If this cannot be accomplished then usually it will be necessary to add insulin therapy to the regimen, often in the form of 2 or more shots of insulin per day. Again, with resolution of the diabetes after delivery, the insulin therapy can generally then be withdrawn. Some moderate regular exercise after meals may also be helpful in controlling blood sugar levels.



Like all other forms of diabetes, the best current monitoring method is the use of home blood glucose self-testing equipment. With a small lancing device and special testing strips, the blood glucose level can be measured directly by the diabetic person herself. These blood sugar levels should be recorded and brought in with the patient when she visits her physician.  Gestational diabetes monitoring sheets are available for download elsewhere on this web site.


Another test to access diabetic control over the 1 to 2 months immediately prior to the date of the test being obtained is a glycosylated hemoglobin level. A glycosylated hemoglobin level measures the per cent(%) of hemoglobin molecules in the blood that have sugar molecules attached. Hemoglobin is the red pigment in red blood cells that helps to transport oxygen. The level of hemoglobin in the blood is constant, but new red blood cells are being continually created and old red blood cells are being continually destroyed. On average, the half life of any hemoglobin molecule in the bloodstream is about 60 days. Sugar molecules in the blood can attach to hemoglobin molecules in such a way that they can't detach themselves, and this is called glycosylated hemoglobin. All of us have a few per cent of the hemoglobin molecules in our blood with sugar molecules attached. This normal range for glycosylated hemoglobin varies from lab to lab but in general is about 4% to 6%. Diabetics, however, who have on average higher than normal blood sugar levels over the last 1 to 2 months (the life span of hemoglobin in the bloodstream) will have more sugar molecules attached to the hemoglobin molecules and therefore have higher glycosylated hemoglobin levels (anywhere from 6% up to about 14%). Diabetics in good control, on the other hand, have normal glycosylated hemoglobin levels.


Revised 8/08



ŠTed A. Tobey, M.D., Inc. ~ All Rights Reserved