Gestational Diabetes: High Blood Sugar in Pregnancy​
Gestational Diabetes: High Blood Sugar in Pregnancy

​​Gestational diabetes or diabetes that develops during pregnancy, affects about 2-5 per cent of pregnant women.

It is common for blood sugar to rise during pregnancy because of hormonal changes. But if your high blood sugar persists, you could develop gestational diabetes mellitus (GDM).

What is gestational diabetes?

The excess blood sugar in the body can harm both the mother and the baby. Gestational diabetes occurs because the body does not produce enough insulin, a hormone which controls blood sugar level. During pregnancy, the placenta produces a number of hormones, some of which may impair the production and function of insulin.

“Usually, gestational diabetes develops after the 20th week of pregnancy,” says the Department of Obstetrics and Gynaecology, KK Women’s and Children’s Hospital (KKH), a member of the SingHealth group. “In most cases, it disappears after the delivery of the baby.”

Risk factors for gestational diabetes

It is not clear why some pregnant women develop gestational diabetes and others don’t. Your risk for developing gestational diabetes increases if you:

  • Are over the age of 25 when you become pregnant

  • Are overweight before you become pregnant

  • Have pre-diabetes before you become pregnant

  • Have a family history of diabetes

  • Have high blood pressure

  • Had a previous pregnancy in which you:

    • Had an unexplained miscarriage or stillbirth

    • Gave birth to a baby who weighed over 4 kg

Symptoms of gestational diabetes

Typically, women with gestational diabetes display no symptoms. Their raised blood sugar level is likely to be discovered during a routine prenatal checkup. However, in some cases, the following symptoms may be present:

  • Increased thirst

  • Increased urination

  • Increased appetite

  • Increased fatigue

Diagnosis of gestational diabetes

Pregnant women who are at high risk for gestational diabetes are likely to be given an oral glucose tolerance test early in their pregnancy, possibly during the first prenatal visit, to screen for diabetes. For other women, the test is usually given between weeks 24 to 28 in their pregnancy.

Ref: R14

Public Events

02 Jul 2025
Programmes KKH Antenatal Programme
1-Day Intensive Course KKH Patient: $306 Non-KKH Patient: $326; 4-Week Course KKH Patient: $240 Non-KKH Patient: $296 Learn More
03 Jul 2025
Talks Health Talk: Nutrition Demonstration @ SHP-Bedok
​Free, no registration required. Please walk in to clinic at specified date and time. Learn More
04 Jul 2025
Talks Health Talk: Weaning Diet @ SHP-Tampines North
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05 Jul 2025
Workshop KKH Child and Infant CPR Workshop
On-site  •  $25 per pax for KK Parenting Club Member; $35 per pax for Non-member Learn More