Arvizu: The Risks and Benefits of The Oral Glucose Tolerance Test

Thursday, January 29, 2015

Erin Arvizu, GoLocal Worcester Health Columnist

The Oral Glucose Tolerance Test (OGTT) has become the standard method for diagnosing gestational diabetes in the United States. It’s typically performed around 24-28 weeks gestation and involves drinking a sugary glucola drink followed by a blood test 1-3 hours later.

If the mother’s blood sugar level registers too high, she will be asked to complete another round of OGTT to either confirm or rule out the presence of gestational diabetes. Because a woman’s body naturally develops a maternal resistance to insulin allowing easier transfer of glucose to the growing baby, there’s some controversy surrounding which blood sugar thresholds should be deemed appropriate. Additionally, the OGTT has quite a low reproducibility rate adding to its potential risk of inaccurate diagnosis.

A woman labelled with gestational diabetes could face an increased risk of induction, while an undiagnosed woman may not have access to the counseling or medication needed to control her blood sugar levels. Despite the lack of evidence proving the OGTT is the best approach to diagnosing gestational diabetes, it remains a standard test that almost all pregnant women encounter in the US.

Kristen Brochu lives quite an active lifestyle and has continued exercising regularly throughout her pregnancy. At 28 weeks gestation, Kristen underwent the OGTT. “I was told this is a standard test and here are the instructions,” Brochu explained. “I had no questions or concerns because I simply believed standard meant required and minimal risk.” Kristen drank the glucola drink and underwent the bloodwork with minimal side effects although her initial reaction after drinking it left her feeling “lightheaded and floaty.” The ingredients in the glucola drink vary by brand, but many have been known to contain some unhealthy ingredients such as brominated vegetable oil, phosphates and artificial colors.

Ashley Makridakis didn’t want to consume the standard glucola drink based on those facts, however, she felt the test would be beneficial based on her family’s history of diabetes, which can increase a woman’s chance of developing it. “I requested I drink an all-natural sugar juice that I heard about instead of that orange one full of yellow 5 and other chemicals,” Makridakis said. Her OB office was willing to meet her request and she said she felt totally fine after drinking it.

Although the test itself may be controversial, most healthcare providers agree reducing high blood sugar levels is beneficial during pregnancy. As with every medical test, patients should be provided full informed consent to weigh the risks and benefits with each test. Some Certified Professional Midwives approach the topic of gestational diabetes from a different angle. Nutrition and exercise are emphasized at every prenatal appointment and if appropriate and consented to, the client may measure blood sugar levels through a finger prick to monitor a series of blood glucose levels both at morning/fasting and after regular meals. This meal approach is also thought to be more reproducible than the OGTT.

Talking with your healthcare provider is the only way to determine the best plan of action regarding your risk and diagnosis of gestational diabetes.

Erin Arvizu is the owner of Wild Orchid Baby at 490 Shrewsbury Street in Worcester. If you need help exploring your birth options, stop by and chat with local birth professionals and childbirth educators.