Testing During Pregnancy Helps Protect Moms and Babies
As if morning sickness and swollen ankles weren't enough, pregnancy changes the way insulin works. Some women develop gestational diabetes, a condition in which a woman without previously diagnosed diabetes exhibits high blood-glucose levels during pregnancy, as a result of this change.
Gestational diabetes is thought to effect 2 to 10 percent of all pregnancies, according to the American College of Obstetricians and Gynecologists (ACOG). It does occur in women who have no risk factors. But, it is more likely in women who:
° are older than 25 years
° are overweight
° have had gestational diabetes before
° have had a very large baby
° have a close relative with diabetes
° had problems in a previous pregnancy (such as stillbirth)
° are Native American, Asian, Hispanic, African American, or Pacific Islander
° have polycystic ovary syndrome (an endocrine disorder)
All pregnant women are screened for these risk factors. If you are at higher-than-normal risk, your blood-glucose level is measured early in pregnancy. If you don't have risk factors, you may be tested between 24 and 28 weeks of pregnancy. It's a simple test. You drink a sugary liquid, then a blood sample is drawn. The glucose level is measured. If the level is high, more tests are done to find out if you have gestational diabetes.
Experts aren't sure what causes gestational diabetes, but they have some ideas. The placenta supports the baby as it grows. Hormones from the placenta help the baby develop. But, these hormones also can block the action of the mother's insulin in her body. This resistance makes it hard for the mother's body to use insulin. She may need up to three times as much insulin as she would when she isn't pregnant. Without enough insulin, glucose can't leave the blood and be changed to create energy, so it ends up remaining in the blood at high levels. This is called hyperglycemia.
Gestational diabetes usually effects the mother in late pregnancy, after the baby's body has been formed, but while the baby is busy growing. So it doesn't cause the kinds of birth defects sometimes seen in babies whose mothers had diabetes before pregnancy.
But, untreated or poorly controlled gestational diabetes can hurt the baby. The mother's pancreas works overtime to produce insulin, but the insulin does not lower the blood-glucose levels. Although insulin doesn't cross the placenta, glucose and other nutrients do. So, extra blood glucose goes through the placenta, giving the baby high blood-glucose levels. This causes the baby's pancreas to make extra insulin to get rid of the blood glucose. Since the baby is getting more energy than it needs to grow, the extra energy is stored as fat.
This can lead to an overly large baby with potential health problems including a damage to their shoulders during birth. Because of the extra insulin made by the baby's pancreas, newborns may have very low blood-glucose levels at birth and a higher risk for breathing problems. Babies with excess insulin can become children at risk for obesity and adults at risk for type 2 diabetes.
A woman with gestational diabetes should start treatment quickly including special meal plans and scheduled physical activity. Treatment also may include daily blood-glucose testing and insulin injections. Prompt treatment helps lower the risk of a Cesarean section, which very large babies may require. Gestational diabetes usually goes away after delivery. But, once a woman had had it, her chances are two in three that it will return in future pregnancies, says the ACOG.
While gestational diabetes is cause for concern, if you are diagnosed with it, you and your doctor should work together to lower your high blood-glucose levels. With this help, you can turn your concern into a healthy pregnancy for you and a healthy start for your baby.