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About one in 25 women who become pregnant develop gestational diabetes, or diabetes during pregnancy, a condition in which the blood sugar level becomes higher than normal. Today, diabetes is one of the most common medical complications of pregnancy.

Diabetes puts a woman into the high-risk group for potential medical problems for her baby and herself. However, with close supervision and tight blood-sugar control, there usually is an excellent outcome—a healthy baby and a mother with a normal blood sugar level after delivery.

"With today’s emphasis on early detection through routine blood tests, and immediate follow-up and education to control blood glucose, essentially all diabetes-related problems are preventable," says endocrinologist Douglas Zlock, MD, director of the outpatient diabetes services at John Muir Health.


Diabetes is a disease in which the body does not produce or properly use insulin, a hormone made in the pancreas. Insulin is necessary as a "key" to allow glucose, the sugar that comes from our food, to leave the bloodstream and nourish our cells.

Without insulin, the blood sugar level rises, and it finally spills into the urine and is eliminated from the body. When not controlled, diabetes can lead to serious health problems including heart and kidney disease, blindness, nerve damage, and foot and leg problems.

Women with pre-existing diabetes, either Type 1 or Type 2, have a special need to closely monitor their blood sugar levels before and during pregnancy.

To control diabetes, you must keep blood sugar levels from becoming too high or too low. To do this, you have to balance food intake with exercise and medication (insulin is the only approved medication during pregnancy).

Risk factors for Gestational Diabetes

Pregnant women who are older than 25, obese, or have a family history of diabetes are more likely to develop diabetes during pregnancy. But it can happen to any woman. It usually appears between the 24th and 28th weeks of pregnancy.  Your obstetrician will screen for gestational diabetes at this time, or even earlier in the pregnancy if increased risks are identified.


The baby may grow too large if the mother has untreated diabetes. This can result in prematurity, trauma during delivery, and a higher chance of a C-section delivery. The baby may also develop an oversupply of insulin, resulting in a low blood sugar reaction at birth.

More than 90 percent of women with gestational diabetes regain normal blood sugar levels after delivery. But diabetes is more likely to reoccur in later pregnancies and may return later in life, especially in women who are overweight.

Key to success

"Today, we are more aggressive about controlling blood glucose levels, as our guidelines have changed to optimize outcomes," says Douglas Zlock, MD, an endocrinologist and medical director of the Diabetes Center at John Muir Health.

"The key factors are better glucose control through diet, exercise, and medication," he adds. "If we cannot achieve good control with diet and light exercise, we use insulin therapy."

Our positive outcomes are the result of our team approach to treatment of women with gestational diabetes. "The best way to deliver care is through a multi-disciplinary program.  Our team includes you, your OB, and our certified diabetes educators – both RNs and registered dietitians.  This type of approach improves the likelihood of a positive outcome for both mom and baby.

Healthy Happenings

John Muir Health offers a team-based program for women who have diabetes prior to becoming pregnant as well as those who develop gestational diabetes.

Diabetes and pregnancy program at John Muir Health: (925) 941-5076

The American Diabetes Association recognizes the program for providing quality patient education.

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