Most women find out they have gestational diabetes because they have a special test done in diabetes called a one hour glucose tolerance test or "1 hr GTT". This involves drinking around 50 grams of glucose in the doctor's office. The blood sugar is tested one hour after drinking the liquid. If this test is elevated further tests are performed to confirm the diagnosis of gestational diabetes.

Women with gestational diabetes normally just need to watch their weight gain and their sugar intake while the doctor does closer monitoring of the pregnancy. Very rarely, the woman will need to take insulin during the pregnancy to keep the blood sugar down.

The biggest complication of gestational diabetes is that of having infants which are larger for their gestational age. Large babies have a higher incidence of having to be born by Cesarean section and there is a higher risk of birth trauma or complications. Just because the infant is big doesn't mean the infant is mature. The baby can weigh ten pounds but still be born with immature lungs.

There are more problems with the pregnancy in gestational diabetes. Frequent tests called fetal non-stress tests must be done to make sure the baby is still healthy. Anytime the non-stress test is not showing normal fetal activity, the infant may have to be delivered early, even if he or she is not particularly full term yet.

After the pregnancy complicated by gestational diabetes, the infant can have problems with very low blood sugar. This is because its pancreas has been putting out insulin in high amounts during the pregnancy-amounts of insulin that are not needed after the baby is born. The blood sugar can become so dangerously low that the baby will need to have intravenous sugar for a period of time until the pancreas settles down. In milder cases, the blood sugar is monitored carefully while the infant is fed formula as early as possible to bring the blood sugar up.

Babies born from mothers with gestational diabetes will have a higher risk for breathing problems after birth. After a few days of oxygen and monitoring, the baby generally resolves without incident. As the baby is born fat, it is at risk for developing obesity of childhood and all of the complications that go with that. As adults, these children are at risk for developing gestational diabetes or type II diabetes themselves.

Once a woman has gestational diabetes, she is at risk for developing the condition again. She is also at risk for developing type II diabetes. If she gets pregnant without controlling her type II diabetes, there is a higher risk of birth defects in the developing infant who was exposed to higher than normal blood sugars during key stages of embryonic development.