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Glucose Challenge Test 50g

Also known as 1 hr Obstetrical

You need to provide

Blood

This test is for

Female

Test Preparation

Intake of glucose solution (50 gms of glucose dissolved in 300 ml of water) is required one hour before the blood sample collection.

Understanding Glucose Challenge Test 50g

What is Glucose Challenge Test 50g?

The glucose challenge test (GCT), also called the one-hour glucose tolerance test, measures your body's response to sugar (glucose). This test is performed during pregnancy to screen for gestational diabetes (diabetes that develops during pregnancy). GCT can be done as early as your first prenatal visit if you're at high risk of gestational diabetes due to obesity, a personal history of gestational diabetes, and a family history of diabetes. A blood sugar level of 140 mg/dL or higher might indicate gestational diabetes.

Most women who have gestational diabetes deliver healthy babies. However, without careful management, gestational diabetes can lead to various pregnancy complications such as high blood pressure, increased risk of having a baby with an excessive birth weight and chances of a C-section delivery.

What is Glucose Challenge Test 50g used for?

The Glucose Challenge Test is performed to:

Screen for high blood sugar in presence of risk factors for diabetes in pregnancy
Detect gestational diabetes

Interpreting Glucose Challenge Test 50g results

Interpretations

Normal range: Less than 130 to 140 mg/dL (7.2 to 7.8 mmol/L)

Gestational diabetes:

A cut-off value of 140 mg/dL (7.8 mmol/L) identifies 80% of women with Gestational diabetes.

A cut-off value of 130 mg/dl (7.2 mmol/L) identifies 90% of women with Gestational diabetes.

Blood sugar levels higher than the normal range indicates increased blood sugar due to the inability of the body to process it.

GCT is a screening test for Gestational diabetes and continuously raised blood sugar levels in subsequent tests indicate a strong possibility of gestational diabetes. Further tests like 2-hour or 3-hour Glucose Tolerance Tests (GTT) are performed to diagnose Gestational diabetes.

Answers to Patient Concerns & Frequently Asked Questions (FAQs) about Glucose Challenge Test 50g

Frequently Asked Questions about Glucose Challenge Test 50g

Q. Is there any preparation required before the test?

Inform the doctor about the medications you may be taking. No other specific preparations are usually required before this test.

Q. How is GCT performed?

This test is performed on a blood sample. A syringe with a fine needle is used to withdraw blood from a blood vessel in your arm. The healthcare provider will tie an elastic band around your arm to make the blood vessels swell with blood and may ask you to make a tight fist. Then he will clean the elbow area over the blood vessel with an antiseptic solution. After that, he will insert the needle into your blood vessel. You will feel a tiny pinprick during the procedure. Blood sample once collected will then be sent to the laboratory. For the GCT that can be performed at any time of day and does not require fasting, you consume a sugar solution of a known concentration (usually 50 gm glucose dissolved in about 300 ml water), and your blood is drawn to measure glucose levels after one hour.

Q. What additional tests can be prescribed by your doctor in case GCT result is not normal?

Additional tests that may be prescribed in case of abnormal Glucose Challenge test result are: · HbA1c Test · 2 Hour and 3 Hour Glucose tolerance Tests · Postprandial Glucose Test · Urine Glucose Test · Lipid Profile Test

Q. What is Gestational Diabetes?

Gestational Diabetes is a condition where blood sugar levels in a non-diabetic woman rise to higher than normal levels during pregnancy. This is caused primarily by hormones secreted during pregnancy which causes insulin resistance by inhibiting cellular signaling mechanisms, thereby preventing cells from effectively taking up and utilizing glucose from blood. This leads to increased levels of blood glucose in the body. The condition is usually resolved after delivery of the child and blood sugar levels return to normal. However, in some cases, gestational diabetes carries a high risk of developing Type 2 Diabetes in the woman. Gestational diabetes also carries a risk of complications during pregnancy and childbirth if blood sugar levels are not managed correctly.

Q. How can Gestational Diabetes affect the baby?

Gestational Diabetes can have a pronounced negative impact on the health of the newborn. Some conditions that may affect the newborn if the mother suffers from unmanaged gestational diabetes include persistent hypoglycemia (low blood sugar levels) in the newborn, hypocalcemia (low blood calcium levels, and hypomagnesemia (low blood magnesium levels). It can also lead to increased birth weight, jaundice, polycythemia (high red blood cell mass), incomplete development of the respiratory system, and birth defects in the newborn.

Q. What are the risk factors for Gestational Diabetes?

The risk factors for Gestational diabetes include being overweight or obese before pregnancy together with low physical activity, having a blood relative already diagnosed with Diabetes, having been diagnosed with gestational Diabetes previously or having delivered a baby weighing more than 4kg. Additionally, if the mother is diagnosed with prediabetes before pregnancy, Polycystic Ovarian Syndrome (PCOS), or hypertension. Gestational diabetes can also be developed if the mother has delivered a stillborn child or one with birth defects; or if she belongs to a high- risk ethnic group like Native American, Pacific Islander, African origin, or South Asian origin.

Q. Is there any risk associated with this test?

There is no risk associated with the test. However, since this test involves a needle prick to withdraw the blood sample, in very rare cases, a patient may experience increased bleeding, hematoma formation (blood collection under the skin), bruising or infection at the site of needle prick.

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