Dhruva Hospitals
Pregnancy & delivery

Sugar test in pregnancy (GDM test): when it is done and what the result means

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Short answer

India’s national guidelines advise every pregnant woman to have a 75 g glucose test at her first check-up, and again at 24 to 28 weeks if the first result was normal. You drink 75 g of glucose and your blood sugar is checked 2 hours later. A 2-hour value of 140 mg/dL or more means gestational diabetes (GDM).

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Dhruva Hospitals, Kadapa

What gestational diabetes is

Gestational diabetes is high blood sugar that develops in pregnancy and usually goes away after the baby is born. It rarely causes symptoms, which is why pregnant women are tested.

Most women with gestational diabetes have healthy babies. Without good control it can make the baby grow larger than usual, add extra fluid around the baby, and raise the chance of pre-eclampsia, early birth, and low sugar or jaundice in the newborn.

How the test is done in India

  1. You do not need to come fasting. Under the National Health Mission guidelines, the test is done whatever time you last ate.
  2. You drink 75 g of glucose dissolved in water.
  3. A blood sample is taken 2 hours later.
  4. A 2-hour value of 140 mg/dL or more is diagnosed as gestational diabetes.

Some doctors and labs use a fasting glucose tolerance test instead, which has different cut-offs. Follow the instructions your doctor gives you.

When it is done

  • At your first antenatal visit, as early in pregnancy as possible
  • Again at 24 to 28 weeks, if the first test was normal
  • About 6 weeks after delivery, if you had gestational diabetes, to check that your sugar has returned to normal

If you have gestational diabetes

  • You will get a diet plan and advice on safe activity, such as walking.
  • You will check your blood sugar regularly.
  • If diet and activity are not enough, you will need tablets or insulin.
  • You will have closer check-ups and scans to follow your baby’s growth.
  • Your doctor will plan the timing of delivery with you.

After your baby is born

Gestational diabetes usually goes away after birth, but it raises your chance of type 2 diabetes later in life. Have your sugar tested after delivery, and keep having regular check-ups even when you feel well.

Common questions

Do I need to fast for the GDM test?

Not for the single-step 75 g test recommended in India’s guidelines; it is done whether or not you have eaten. If your doctor has ordered a fasting test, follow those instructions.

Will my baby be born with diabetes?

No. Gestational diabetes does not mean your baby has diabetes. Good sugar control lowers the risks for your baby, such as growing too large or having low sugar after birth.

Will I need insulin?

Many women manage with diet and activity alone. If your sugar stays high, your doctor will add tablets or insulin, which are safe in pregnancy when prescribed.

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Sources

This article is general information, not a diagnosis or treatment plan. In an emergency, call +91 90368 52311.