Gestational diabetes is high blood sugar that develops during pregnancy. It usually goes away after the birth, but it needs to be managed well because it can cause problems for you and your baby. Here is what to expect from testing, treatment and the months after birth.
Why does it happen?
During pregnancy your body needs extra insulin, the hormone that keeps blood sugar under control. Gestational diabetes happens when your body cannot make enough insulin to meet those extra needs.
Who is more likely to get it?
- A body mass index (BMI) above 30
- A previous baby who weighed 4.5 kg (10 lb) or more at birth
- Gestational diabetes in a previous pregnancy
- A parent or sibling with diabetes
- South Asian, Black, African-Caribbean or Middle Eastern family origin
Many people with gestational diabetes have no symptoms, which is why testing matters.
The glucose test
The usual screening test is an oral glucose tolerance test (OGTT). You fast, have a blood test, drink a sugary drink and have another blood test about 2 hours later. It is usually done between 24 and 28 weeks of pregnancy. If you had gestational diabetes before, you will usually be tested earlier as well.
Treatment
- Checking your own blood sugar with a home testing kit, often before breakfast and 1 hour after meals
- Changes to what you eat, such as cutting down on sugary foods and drinks, ideally with advice from a dietitian
- Regular physical activity, such as walking after meals
- Tablets or insulin injections if diet and activity are not enough
Why control matters
Well-controlled blood sugar lowers the risk of problems such as a very large baby, which can make birth more difficult, and your baby having low blood sugar or jaundice after birth. You will usually have extra checks and scans during pregnancy.
After your baby is born
Gestational diabetes normally goes away after birth, but it raises your risk of type 2 diabetes later in life. In the UK you are offered a blood test 6 to 13 weeks after giving birth, then once a year if the result is normal. Ask your doctor what is recommended where you live.
Keep an eye on healthy weight gain with our Pregnancy Weight Gain Calculator.