Everything You Should Know About Gestational Diabetes

This blood sugar condition can have serious impacts on both mom and baby. Learn how to prevent it, plus signs to watch for.

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During pregnancy, your hormones go through a variety of changes to support your growing baby. For example, your breasts will get bigger to help with milk production, and your joints, especially those around your pelvis, become more relaxed to accommodate your expanding uterus. Pregnancy can even change the way your body processes blood sugar, and in severe cases, some expectant moms can develop gestational diabetes.

"Gestational diabetes causes high blood sugar that can affect your pregnancy and your baby's health," says Jodie Horton, M.D., a fellow of the American College of Obstetricians and Gynecologists (ACOG) and chief wellness advisor at Love Wellness. "Typically, various hormones work to keep your blood sugar in check, but during pregnancy, hormone levels change, making it harder for your body to process blood sugar effectively."

What Is Gestational Diabetes?

Gestational diabetes is a type of diabetes that happens in pregnant women who didn't have a diabetes diagnosis before they became pregnant, according to the Centers for Disease Control and Prevention (CDC).

During pregnancy, your body doesn't tolerate the sugar you're taking in as well as it would when you're not pregnant, which causes gestational diabetes, says Heather Irobunda, M.D., a board-certified obstetrician-gynecologist based in New York City.

Insulin is a hormone produced in the pancreas that keeps your blood sugar levels normal by regulating the way your body converts sugar into energy. But when you're pregnant, the placenta (the organ that supplies oxygen and nutrients to the baby as it grows) releases high levels of pregnancy hormones — estrogen, cortisol, and human placental lactogen, namely — which can interfere with insulin production, making it more difficult for your body to regulate blood glucose, explains Dr. Irobunda.

While gestational diabetes and type 2 diabetes may seem similar at first glance as they are both caused by insulin resistance, they aren't the same thing. "Type 2 diabetes occurs because your body isn't able to properly use insulin to lower your blood sugar," whereas "gestational diabetes develops in pregnant women because their body isn't able to make and use insulin properly," explains Dr. Horton. (

If you're diagnosed with gestational diabetes, there are two classifications: A1 and A2. "A1 can be controlled with diet alone, but A2 needs to be controlled with medication to maintain good blood sugar control," says Dr. Horton.

While gestational diabetes can resolve after childbirth, women with the condition have an increased risk of developing type 2 diabetes postpartum, so it's important to catch it in time and get proper treatment ASAP.

Risk Factors for Gestational Diabetes

Any pregnant woman can develop gestational diabetes, regardless of whether they had prediabetes or type 2 diabetes before pregnancy, explains Dr. Irobunda. Approximately 6 to 9 percent of pregnant women develop the condition, according to the CDC.

Still, some people are at greater risk. Here are some gestational diabetes risk factors that may increase your chances of developing the condition, according to the ACOG:

  • Living a sedentary lifestyle
  • Being overweight or obese
  • Are 35 years old
  • Have had gestational diabetes in a previous pregnancy
  • Previously delivering a baby who weighed 9 or more pounds at birth
  • Having high blood pressure
  • Have a history of heart disease
  • Have polycystic ovary syndrome (PCOS)
  • Are Black, Hispanic/Latino, Native American, Asian, or Pacific Islander

Women who are 35 years or older are at a higher risk for gestational diabetes because of the reduced insulin sensitivity and progressive dysfunction of the pancreas as you age, explains Dr. Horton.

Moreover, BIPOC women are at an increased risk of gestational diabetes compared to white women. Specifically, Hispanic women had 7.7 times greater risk, Asian and Pacific Islander women 6.3 times greater risk, and Black women 9.9 times greater risk of developing gestational diabetes compared to white women, according to one study published in Diabetologia. (

The exact reason for this race-related risk isn't clear, "but what is known is that BIPOC don't have the same access to health care," says Dr. Horton. "Even women who are financially stable and college-educated are likely to face systemic racism in the health care system leading to preventable medical complications."

And because there is a high rate of obesity and hypertension in BIPOC communities, these risk factors can increase their chances of developing gestational diabetes, she adds. Other contributing factors may be socioeconomic status, housing, and transportation, which all play a big role in having access to nutrient-dense foods and good health care to maintain a healthy pregnancy. (

Gestational Diabetes Symptoms

Gestational diabetes symptoms can include increased hunger and thirst, fatigue, frequent urination, sugar in the urine (detected by a urine test), as well as blurred vision, nausea, vomiting, and weight loss in spite of increased hunger, according to Standford Children's Health. But, oftentimes there are no signs of gestational diabetes or symptoms are very mild. This is why it's important for every pregnant person to get screened for gestational diabetes, or get tested earlier in the pregnancy if they're at high risk. (

Gestational Diabetes Test

Screening for gestational diabetes is recommended for every pregnant person. While gestational diabetes can develop at any point during pregnancy, you are usually screened for the condition between the 24th to 28th week of gestation.

"Screening for gestational diabetes happens during this time in the second trimester because this is when insulin resistance peaks due to hormones produced by the placenta," says Dr. Horton. "However, there is an increased incidence of type 2 diabetes in women of childbearing age, so some women with risk factors will be screened earlier in pregnancy."

There is a one-step or two-step screening for gestational diabetes, according to the U.S. National Library of Medicine. You'll need to consult with your doctor to see which test they recommend for you.

Two-Step Gestational Diabetes Test: The first step is the one-hour glucola test, which doesn't require prior fasting. You consume a very sugary drink, then your blood is drawn an hour later to see how well your body processes the glucose. If your blood glucose score is more than 140, you'll continue on to step two, called the three-hour glucola test, says Dr. Horton.

For this second step, you'll need to avoid eating or drinking anything for at least eight hours before the three-hour glucola test. Your doctor will first draw blood to check for your initial blood glucose level. Then, you drink the sugary beverage. From here, you have your blood drawn every hour for the next three hours. If two out of the four blood test times come back elevated, you are diagnosed with gestational diabetes.

One-Step Gestational Diabetes Test: The two-hour glucola test is a one-step diagnostic. Just as with the three-hour test, you're asked to fast for 8+ hours before the test is administered. You'll have your blood drawn for an initial glucose screening before drinking the same sugary beverage. Then, your blood is drawn at one and two-hour intervals, says Dr. Horton. If one blood sugar test is elevated, you are diagnosed with gestational diabetes.

Gestational Diabetes Complications

Gestational diabetes comes with concerns for both baby and mom and puts you at a higher risk of the following:

Difficult Childbirth

"Pregnancies that are complicated by gestational diabetes are considered high risk and are monitored more closely throughout the pregnancy," says Dr. Horton. "Gestational diabetes that's not well controlled can lead to high blood sugar levels, which can cause problems for mom, including an increased likelihood of needing a C-section to deliver." That's because having high blood sugar levels can cause your baby to grow very large (weighing 9 pounds or more). Delivering a baby of that size vaginally, "can cause injuries to the baby, such as nerve damage to the arm or a broken clavicle," adds Dr. Irobunda. (

In addition, "sometimes, babies of mothers with gestational diabetes have low blood sugar (hypoglycemia) after birth, which can cause seizures in the baby," says Dr. Horton. When mom has elevated blood sugars, so will the fetus, causing the baby to produce excess insulin to keep blood sugars under control, explains Dr. Horton. After birth, the fetus is no longer exposed to elevated blood sugar levels, but in some cases, the newborn can still produce high levels of insulin, which leads to very low blood sugar levels.

Because the newborn may have trouble controlling their blood sugar after birth, the baby may need to stay in the NICU (neonatal intensive care unit) to be monitored by pediatricians, says Dr. Irobunda. According to a study of 766 mothers in the Journal of Clinical Neonatology, infants born to mothers with gestational diabetes had longer hospital stays (about six days) compared to infants of mothers without gestational diabetes (three days).

Gestational diabetes can also cause stillbirth, preterm birth, and serious breathing problems for the baby, per the Mayo Clinic.

High Blood Pressure

Gestational diabetes is also associated with high blood pressure during pregnancy, also known as gestational hypertension. This can lead to preeclampsia, a serious condition during pregnancy marked by the onset of high blood pressure and signs of damage to some organs, typically the liver and kidneys, according to the Mayo Clinic. Left untreated preeclampsia can be fatal to you or your baby. The condition is usually diagnosed after 20 weeks of pregnancy.

Yeast Infections and Bacterial Vaginosis

Moreover, "elevated blood sugars can cause yeast and bacteria to overgrow and increase the risk of vaginal infections," says Dr. Horton. "Yeast and bacteria like to feed off the body's excess sugar. In particular, pregnant women with diabetes also have a weaker immune system and decreased ability to fight off infections such as yeast and bacterial vaginosis." Bacterial vaginosis can also increase the risk of preterm delivery, but it isn't known whether treating it can reduce the chances of such, according to the JAMA Network.

Type 2 Diabetes

"Women who had gestational diabetes during pregnancy have an approximately 50 percent increased risk of developing type 2 diabetes later in life," says Dr. Irobunda. "There is also some evidence to support that it can increase the child's risk of diabetes in the future."

To ensure you don't develop type 2 diabetes postpartum, the CDC recommends getting screened four to 12 weeks after giving birth. And if you don't have diabetes, you should continue to get tested every one to three years to ensure your blood sugar levels are normal.

What's more, having gestational diabetes is associated with developing type 2 diabetes, high blood pressure, and heart disease postpartum, according to a study in PLoS Medicine. Researchers found that women with gestational diabetes were 20 times more likely to develop type 2 diabetes, 2.8 times more likely to develop ischemic heart disease, and twice as likely to develop hypertension within the first few years of postpartum.

How to Prevent Gestational Diabetes

Adopting healthy lifestyle habits before pregnancy will help reduce your overall risk of gestational diabetes, says Dr. Horton. There is no one singular gestational diabetes diet, but "eating foods high in fiber and low in fat, staying physically active, and maintaining a healthy weight before pregnancy can help reduce your risk," she says. Then, "once you are pregnant, don't gain more than the recommended weight."

The recommended amount of weight gain during pregnancy depends on your body mass index (BMI) before pregnancy as well as if you're carrying one or multiple babies, according to the CDC. For example, if you're considered "a normal weight" with a BMI between 18.5 and 24.9, a pregnancy weight gain between 25 to 35 pounds is considered healthy. But if you have a BMI of 30 or higher, then doctors recommend that you gain only 11 to 20 pounds during pregnancy.

Staying active and incorporating exercise into your pregnancy can also help reduce gestational diabetes, gestational hypertension, and preeclampsia, according to a review in the British Journal of Sports Medicine. The ACOG recommends pregnant women should get at least 150 minutes of moderate-intensity exercise each week. That works out to five 30-minute workouts each week.

Consider working with a pre- and postnatal-certified trainer to help you figure out a routine that best fits your lifestyle and goals. Just remember to stop exercising altogether — and reach out to your doctor ASAP — if you experience any bleeding, shortness of breath, chest pain, dizziness, muscle weakness, headache, painful contractions, or fluid leaking from the vagina.

Gestational Diabetes Treatment

Many of the same measures recommended to prevent gestational diabetes are also used for treating it. Following a gestational diabetes meal plan that's rich in fiber will help keep blood sugar levels normal. Women with gestational diabetes can also benefit from following a workout routine with moderate-intensity aerobic exercise and strength training, according to a review in the World Journal of Diabetes. Studies have shown that pregnant women with gestational diabetes who exercise have lower glucose levels and have babies with a lower birth weight than those who didn't exercise as much during pregnancy. (

"Mothers with gestational diabetes need to check their blood sugar four times a day — once after fasting in the morning and again after each meal" in order to keep track of their blood sugar, says Dr. Horton. "Another critical part of the treatment plan is close observation of the baby. Ultrasounds will be done to check the baby's growth and development throughout the pregnancy. If mom is taking medication to lower her blood sugar, the fetal heart rate is also monitored starting in the third trimester." This is done to ensure that the baby isn't in any distress.

Having gestational diabetes might be stressful and scary to any mom-to-be, but under the right care and with the proper screenings, you can have a healthy baby and reduce your risk of birth complications and health issues postpartum.

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