This problem is called insulin resistance. Insulin resistance makes it hard for the mother's body to use insulin. You may need up to three times as much insulin as when you were not pregnant. Gestational diabetes starts when your body is not able to make and use all the insulin it needs for pregnancy. Without enough insulin.
Sugar builds up in the blood to high levels.
This is called hyperglycemia. By then, your placenta has begun to make the hormones that lead to insulin resistance. The screening test measures your blood sugar response to glucose consumed in a drink. How Gestational Diabetes Can Affect Your Baby G estational diabetes affects the mother in late pregnancy, after the baby's body has been formed, but while the baby is busy growing. Because of this, gestational diabetes does not cause the kinds of birth defects sometimes seen in babies whose mothers had diabetes before pregnancy.