Gestational diabetes (GDM) is diabetes you have while you’re pregnant if you didn’t have diabetes before. GDM starts when your body is not able to use the insulin it needs while you’re pregnant. Without enough insulin, blood glucose (blood sugar) can’t be moved from your blood for your body to use as energy. This leads to high blood glucose levels (hyperglycemia).
GDM causes your pancreas to produce more insulin, but the insulin isn’t able to lower your blood glucose levels. The insulin your body makes doesn’t cross the placenta to your baby, but glucose and other nutrients do. This gives your baby high blood glucose levels while you’re pregnant. The high blood glucose levels cause the baby's pancreas to make extra insulin to process the blood glucose. Since the baby is getting more energy from the extra blood glucose than it needs, the extra energy is stored as fat.
How does gestational diabetes affect the baby?
GDM affects you later in your pregnancy (during the second or third trimester) after the baby’s body has formed but is still growing. This means your baby will not be affected the same as the baby of someone who had diabetes before they were pregnant.
If you have GDM your baby will be at higher risk of:
- Macrosomia, or a larger baby at birth
- Macrosomia can lead to damage to your baby’s shoulders during birth
- Low blood glucose levels (hypoglycemia) at birth
- Breathing problems at birth
- Being born early or stillborn
- Obesity and type 2 diabetes later in life
Learn how to treat GDM to keep you and your baby healthy.
