Gestational diabetes: What to know when blood sugar is too high during pregnancy
This common condition affects many women during pregnancy, even if they weren’t diabetic before.
Gestational diabetes is diabetes that occurs in pregnant women. It means that your blood sugar level is too high. During pregnancy, certain hormones cause this to happen.
While any pregnant woman can potentially develop gestational diabetes, it is more likely in women who are overweight, have a family history of diabetes or have had history of a baby weighing more than 9 pounds at birth. Additionally, if you have had gestational diabetes in the past or had pre-diabetes before your pregnancy, you are more likely than other women to develop gestational diabetes.
How does gestational diabetes happen?
Your body turns food into sugar (glucose) to use for energy. This glucose goes into your bloodstream. Your body then releases a hormone called insulin to help your body move glucose out of the bloodstream and into the cells, where it fuels basic cellular functions.
Glucose goes from mother to baby through the placenta. The baby uses this sugar to grow, but sometimes the placenta prevents insulin from working properly in the mother’s body, which can result in the mother’s glucose level rising too high. This can cause problems for the mother and the baby.
What are the risks of gestational diabetes for me and my baby?
Mothers with gestational diabetes have a greater chance of developing preeclampsia (high blood pressure during pregnancy); infections in the urinary tract and vagina; and having very large babies. The baby’s excessive size is called macrosomia. If the baby is too large, childbirth can injure the mother, who may need to have a cesarean section to deliver the baby safely. Your doctor will talk to you about a possible cesarean section so you’ll know what to expect. Occasionally, gestational diabetes can also cause too much fluid to collect around the baby in the womb, which can cause discomfort and preterm labor.
The mother could possibly develop low blood sugar — hypoglycemia — instead, because so much insulin moves into the baby’s bloodstream. However, the most serious risk of gestational diabetes is the death of the fetus, if the mother’s blood sugar stays too high for too long.
How do we screen for and diagnose gestational diabetes in pregnancy?
Screening usually occurs at your 24- to 28-week prenatal visit. Your doctor will give you a fluid to drink (usually orange- or lime-flavored) that contains concentrated glucose. An hour after you drink it, you’ll have your blood sugar checked. If the glucose value of your blood is higher than 140 mg/dl (140 milligrams of glucose per deciliter of blood), you will need to come back for a three-hour glucose check. During this test, your blood glucose is tested one hour, two hours and three hours after you drink the solution. If two or more of these values show elevated blood glucose, you are diagnosed with gestational diabetes.
It is important to note that women who are obese or have a history of gestational diabetes with a previous pregnancy may have glucose screening done earlier in the pregnancy, during the first trimester.
What if I am diagnosed with gestational diabetes?
If you screen positive for gestational diabetes, you will be referred for an appointment with a diabetes educator, who will teach you how to check your blood sugar levels daily. You will also learn about the symptoms of high and low blood-sugar levels.
You are encouraged to work with a nutritionist, who can help you choose the proper foods to eat during pregnancy to manage your blood sugar levels.
Do I have to take medication if I am diagnosed with this?
The majority of first-time gestational diabetics can control their blood sugar with diet and exercise. However, some women continue to have elevated blood sugar despite following a healthy diet and getting exercise. For these women, medication is recommended.
Insulin is considered to best first-line treatment for controlling blood sugar during pregnancy. However, this can require injecting yourself with medicine up to four times per day. Patients significantly fearful about needles can try oral medicines first, usually metformin or glyburide.
Am I at increased risk for diabetes after pregnancy?
About 5 percent of patients who have gestational diabetes in pregnancy will develop diabetes after pregnancy and should be checked for this six to 12 weeks after delivery.
To minimize your risk, continue to take care of yourself. Additionally, breastfeeding helps lower your blood sugar. Keep your weight down by eating foods that are low in fat and sugar and continue regular exercise.
This post was written by Emad Elsamadicy, M.D. Raised in Tuscaloosa, Ala., he graduated from UAB School of Medicine in 2013 and completed his OB-GYN residency at Vanderbilt University Medical Center in 2017. He is an assistant professor of Obstetrics and Gynecology at Vanderbilt University Medical Center.