Cause

During pregnancy, an organ called the placenta develops in the uterus. The placenta connects the mother and baby and makes sure the baby has enough food and water. It also makes several hormones. Some of these hormones make it hard for insulin to do its job—controlling blood sugar—so the mother's body has to make more insulin to keep sugar levels in a safe range. Gestational diabetes develops when the organ that makes insulin, the pancreas, cannot make enough insulin to keep blood sugar levels within a target range.

Symptoms

Because gestational diabetes does not cause symptoms, you need to be tested for the condition. This is usually done between the 24th and 28th weeks of pregnancy. You may be surprised if your test shows a high blood sugar. It is important for you to be tested for gestational diabetes, because high blood sugar can cause problems for both you and your baby.

Sometimes, a pregnant woman has been living with diabetes without knowing it. If you have symptoms from diabetes, they may include:

• Increased thirst.
• Increased urination.
• Increased hunger.
• Blurred vision.

Pregnancy causes most women to urinate more often and to feel more hungry, so having these symptoms does not always mean that a woman has diabetes. Talk with your doctor if you have these symptoms, so that you can be tested for diabetes.