Diabetes develops when the body is unable to produce or properly use a hormone called insulin that helps regulate blood sugar levels, also known as glucose levels. Gestational diabetes is a type of diabetes that occurs during pregnancy.
In gestational diabetes, the placenta that supplies nutrients to the growing baby produces hormones that interfere with insulin production, so blood sugar levels are not properly controlled. As a result, the mother’s blood glucose levels rise, and the excess sugar in her blood is passed on to the baby.
Gestational diabetes can affect the mother and developing baby in several ways:
- The mother may have an increased risk of high blood pressure or preeclampsia, a serious complication that may lead to seizures.
- The baby’s extra blood glucose is stored as fat, so the baby gains much more weight than normal. This can lead to a difficult delivery or possibly a premature birth.
- The baby’s pancreas will produce extra insulin to try to lower blood sugar levels, which may result in very low blood glucose levels at birth, along with an increased risk of breathing problems.
- Babies born with excess insulin are more likely to be obese as children and develop type 2 diabetes as adults.
Several factors may increase the risk of gestational diabetes. Some risk factors are the same as type 2 diabetes, such as being overweight and eating food high in carbohydrates or sugar.
“Unlike type 2 diabetes, the mother’s age can be a risk factor for gestational diabetes,” says Sean Daneshmand, MD, an OB-GYN who specializes in maternal and fetal medicine and high-risk pregnancies at Scripps Clinic. “Many women are becoming pregnant after age 35, which can increase their risk of diabetes in pregnancy.”
Women with a family history of gestational diabetes also have a greater risk, as do women whose diabetes risk was higher before pregnancy.
In many cases, gestational diabetes has no symptoms. If symptoms do occur, they may include the following:
- Frequently needing to urinate
- Feeling thirsty even after drinking more fluids than normal
- Feeling more tired and fatigued than usual
- Dry mouth, despite drinking a lot of water
- Nausea and vomiting beyond “morning sickness”
- Weight loss, despite having an increased appetite
- Blurred vision or other vision problems
- Yeast infections
Because many women with gestational diabetes do not experience any symptoms, obstetricians will screen for the condition as part of their prenatal care. Typically, women whose risk is average will have a gestational diabetes screening test between 24 and 28 weeks of pregnancy. Women with an increased risk of gestational diabetes may be tested earlier.
During the initial screening, the mother drinks a sugary solution; an hour later, the doctor measures her blood glucose levels. If they are higher than normal, the next step may be a three-hour sugar test, where blood sugar levels are tested multiple times over a three-hour period.
Fortunately, gestational diabetes is treatable. For most women, treatment involves managing their blood sugar levels through dietary changes, including eating a healthy, low-sugar and low-carbohydrate diet. Exercise is also important.
Women may need to test their blood sugar levels at home several times a day to ensure they aren’t too high. If diet and exercise aren’t enough to control glucose levels, their doctor may recommend medication or insulin injections. For most women, blood sugar levels return to normal following delivery or shortly thereafter.
“Scripps has a care management program especially for women who develop gestational diabetes,” says Dr. Daneshmand. “In addition to maternal fetal medicine physicians, we have nurses who are certified diabetes educators, nutritionists and endocrinologists who specialize in managing this condition.”