Gestational diabetes (GD) is diabetes that develops for the first time during a woman’s pregnancy. It most commonly occurs about halfway through pregnancy (from 20 to 24 weeks).

It is often diagnosed by a screening blood test and may be suspected when a pregnant woman is exhibiting symptoms of high blood sugar such as increased thirst, fatigue, urination and weight loss. These symptoms may be attributed to pregnancy and that is why a blood test is very important to confirm the diagnosis.

Gestational diabetes is treated with diet and medications such as insulin. It poses increased risks of short- and long-term health problems for both the mother and the developing infant.

Health Problems for Mother and Child

Pregnant women with GD are at increased risk of developing elevated blood pressure, preeclampsia during pregnancy, and type-2 diabetes after the pregnancy.

A higher Body Mass Index (BMI) before pregnancy was the strongest individual risk factor for developing gestational diabetes.

High blood sugar is also a risk for a woman's unborn baby. It is considered to be a teratogen — a substance that causes birth defects. Infants born to mothers with gestational diabetes may be excessively large, making delivery more difficult.

In addition to birth defects, these infants have an increased risk of elevated bilirubin and jaundice and may have difficulty with blood sugar control themselves. They are also at higher risk for developing diabetes later in life.

For all these reasons, gestational diabetes is a condition well worth avoiding, and fortunately, it is something many pregnant women can avoid. Recent research sheds some light on some of the ways women can control or decrease their risk of developing GD.

The Study
To understand how certain health habits, practiced before pregnancy, worked together to impact the risk of gestational diabetes, researchers followed a group of women who were free of chronic illness throughout a 10-year study period.

Women were asked about their pre-pregnancy exercise habits (optimum was defined as at least 150 minutes/week), their weight, healthful diet, and smoking history.

The women had over 20,000 live, single baby births over the 10-year period.

The results offer some good news about one’s ability to reduce the risk of gestational diabetes.

Simple Steps to Reduce Your Risk

There were few surprises in the health behaviors that reduced a woman's chances of developing diabetes during pregnancy. A higher Body Mass Index (BMI) before pregnancy was the strongest individual risk factor for developing gestational diabetes.

Four health factors cut your risk for gestational diabetes in half.

Even when BMIs were just at the high end of normal (23.0-24.9) there was a significant increase in the risk of developing gestational diabetes.

Each of the other lifestyle factors — exercise, diet and smoking — were significant risk factors when poor habits, such as frequently eating fried, fast foods, were part a woman's lifestyle before becoming pregnant.

If women began to eat better, exercise more and lose weight prior to becoming pregnant, the effect was especially protective. The more healthful habits reported, the lower the risk of GD.

When three healthy life style factors were reported, there was a 40% lower risk of developing GD. This increased to 50% lower risk when all four were reported. Furthermore, compared with women who reported none of the four health factors measured in the study, those who reported all four had an 80% reduced risk of developing diabetes while pregnant.

The message is clear. While not wholly preventable, the risk of gestational diabetes can be greatly reduced by paying attention to these health factors prior to pregnancy: Not smoking, eating a healthful diet, maintaining a healthful body weight, and exercising an average of 30 minutes per day at least 5 days a week. These are all achievable goals for most women.

You probably have noted that these same lifestyle factors are beneficial for the prevention of cardiac disease, metabolic syndrome, and many chronic and disabling diseases. Now women have an additional reason to maintain healthy lifestyles.

The study is published in BMJ, the British Medical Journal.