A pregnant woman with diabetes is classified by when she was diagnosed. If diabetes was present prior to pregnancy, it is pregestational and can be either type 1 (insulin-dependent, or juvenile) or type 2. As the average age of onset for type 2 diabetes is over 40, it is an uncommon classification in pregnancy. Gestational diabetes is a condition of abnormal carbohydrate metabolism that is diagnosed during pregnancy. Mothers diagnosed with gestational diabetes usually are not diabetic after giving birth. However, untreated or poorly controlled diabetes can have a serious impact on the health of both mothers and babies.
Premature Birth
In gestational diabetes, sugar levels that remain high in the mother's bloodstream cross the placenta. The baby's body responds by producing increased insulin. Over time, the mother's diabetes makes the baby fat and the placenta large, and causes the amniotic fluid volume to expand. Prenatally, the mother's abdomen measures too large for her corresponding gestational dates. Polyhydramnios, or too much amniotic fluid, is likely to trigger labor before the baby is fully developed. Babies born prematurely may suffer respiratory distress, have increased vulnerability to infections, experience difficulty regulating temperature and blood glucose, and may become jaundiced due to liver immaturity. They are also at risk for disabling side effects of medications and developmental delays.
Cesarean Delivery
Infants born to gestationally diabetic mothers are typically high-birth-weight babies. Surgical delivery of very large infants is frequently necessary, due to a disproportion between the baby's head and the mother's pelvis. Risks of surgery include anesthesia complications and infections. Mothers who have gestational diabetes are very likely to have the condition with subsequent pregnancies and to give birth to increasingly larger infants.
Neonatal Hypoglycemia
The infant of a mother with gestational diabetes will have special risks and problems related to his size. When the umbilical cord is clamped and cut after birth, the infant of a diabetic mother stops receiving high levels of blood sugar. This can be a dire situation for the baby, who may still be producing excess insulin. Blood sugar can drop quickly to dangerously low levels, which can affect breathing and other bodily functions. Neonatal hypoglycemia, or low blood sugar in a newborn infant, can lead to brain damage if not corrected. For this reason, most hospitals monitor the blood sugar of all infants with a birth weight of over 8 lb. 13 oz., or approximately 10 percent of newborns.
Vascular Changes
Over time, high blood sugars damage blood vessels and impair circulation. These vascular changes explain why pregestational diabetes is associated with low-birth-weight infants, instead of large babies and expanded amniotic fluid. Birth defects of the heart and spine among babies born to diabetic women may be due to high blood glucose during the first trimester of pregnancy. Vascular changes increase the risk of vision loss and kidney disease, both of which can be made worse by the physiological demands of pregnancy, especially if the mother has been diabetic for more than two years. Severe kidney disease can lead to stillbirth.
References
- "Holistic Midwifery"; Anne Frye, 1998
- Children's Hospital of Boston: Newborn Hypoglycemia
