What is Gestational Diabetes?

Pregnancy has great demands on the carbohydrate metabolism. It causes the insulin requirements in the human body to change as it progresses even in a healthy pregnant woman. Maternal glucose, in which the fetus relies on it as a chief fuel source, crosses the placenta but insulin does not because pregnancy activates the protective mechanisms that have anti – insulin effects. The “so – called” protective mechanisms also increased hormone production (placental lactogen, estrogen and progesterone) and prolonged elevation of stress hormones ( cortisol, epinephrine and glucagon) in which it raise blood glucose levels.

In a normal pregnancy, there is a balance between an increase in anti –  insulin factors and an increase in insulin production to maintain normal blood glucose levels. However, pregnant women who are pre- diabetic or diabetic cannot make enough insulin to overcome the insulin antagonist mechanisms of pregnancy.

In a pre-diabetic or diabetic pregnant patient, the maternal insulin needs decrease during the first trimester. Then for the period of second and third trimesters, the insulin demand increases in placental hormones necessitating an increase in the patient’s insulin dose. After the placental delivery, placental hormones drop quickly and so the insulin requirements also decrease.

Gestational Diabetes Causes

Gestational diabetes takes place during the second or third trimester in pregnancy in 2% – 3% women who do not have a previous diagnosis as diabetic, and occurs when the insulin resistance becomes most obvious because the pancreas cannot respond to the demand for more insulin.

The clear cause of gestational diabetes is unknown. Some claimed it is the result from inadequate insulin response to carbohydrate or from excessive response to insulin or both. Women are at risk for gestational diabetes when they are obese, more than 25 years old, have a family history of diabetes in first degree relatives or a member of an ethic group ( e.g. Asian, American, Native American, Hispanic), have history of perinatal loss, multiple gestation /large babies ( 9 – 10 pounds or more) or congenital anomalies in previous pregnancies.

Gestational Diabetes Symptoms

Symptoms of gestational diabetes like other types of diabetes include the three “P’s”:

• polyuria (increased urination due to the excess glucose of the body)
• polydipsia (increased appetite/hunger for the cells are starving because of cellular starvation)
• polyphagia (increased thirst due to dehydration because of frequent urination)

Other warned signals to a woman with gestational diabetes include unusual weight loss, sudden changes in vision, recurrent urinary tract infections and vaginal yeast infections, fatigue and weakness, irritability, numbness or tingling in hands or feet, dry skin and skin wounds that are slow to heal.

Gestational Diabetes Prevention

To prevent women to have gestational diabetes, they should seek medical consult for selective screening of it during pregnancy. Women who are considered to be at high risk of the gestational diabetes should be screened earlier or at their first prenatal visit and again at 24^th to 28^th weeks of gestation. Uncontrolled diabetes in pregnant women may predispose infants after birth may be large in size and predisposed for hypoglycemia (less amount of glucose in the blood because the fetus after delivery, produces its own insulin and gets glucose from the mother), hyperbilirubinemia (excess of bilirubin in the blood), respiratory distress sydromne, hypocalcemia and congenital anomalies.

Gestational Diabetes Testing

The common diagnostic tests that are performed to know if a pregnant woman have gestational diabetes or not are glucose screening test, three hour glucose tolerance test and glycosylated hemoglobin test.

In glucose screening test, the patient must have an eight hour fasting for FBS (fasting blood sugar), should be given a 50- g glucose load at weeks 24 to 28 of pregnancy and blood sample is taken for sugar 1 hour after . This test may be repeated again at 32 weeks or if the woman is obese or aging more than 40 years old.  The patient is diagnose to have gestational diabetes if the FBS result is more than 90 mg/dl and at 1 hour post glucose loading is more than 140 mg/dl. So, if that is the serum glucose at 1 hour, client is scheduled for a 100-g three hour fasting glucose tolerance test. If two of the blood samples are not in the normal value or above 95 mg/dl, a diagnosis of gestational diabetes can be made by a professional doctor. On the other hand, glycosylated hemoglobin measures control after three months.  Upper normal level is 6% of total hemoglobin.

Managing Gestational Diabetes

If a pregnant woman is positive to have gestational diabetes, she must have a proper diet: 20% of calories from protein, 50% from carbohydrates, 30% from fats and must increased dietary fibers. In addition, she must exercise to lower blood glucose and should have stress management.  Insulin must be given too if diet cannot control glucose levels in the blood. The clinical practitioners on the other hand must ascertain to do interventions to a gestational diabetic woman like monitoring weight, assessing for maternal complications, monitoring signs of infection, administering insulin as ordered or instructing on self – administration and assessing the fetal status appropriately.

During labor, a gestational diabetic patient must be monitored continuously as well as the fetus because labor depletes glycogen. In the postpartum period, a mother should be closely observed for hypoglycemic reactions since there is a sudden drop in insulin requirements that normally occurs (in which the gestational diabetic patient may not need insulin for the first 24 hours).

Also Read:

• Symptoms of Diabetes Mellitus Type 1, Type 2 & Gestational
• Causes of Diabetes
• Type 1 Diabetes Symptoms and Signs
• Type 2 Diabetes Causes
• Diabetic Heart Attack Symptoms : Diabetes symptoms

by Dr John on 01. Sep, 2010 in Diabetes