Description, Causes and Risk Factors:
Diabetes or diabetes mellitus is a metabolic disorder characterized by hyperglycemia (high blood glucose levels) caused by impairment in insulin secretion and/or action. Pregnant women with existing diabetes referred to as pre-gestational diabetes.Pregestational diabetes prevalence continues to rise largely due to increases in type II diabetes associated with obesity. Pregestational diabetes is a major cause of maternal and perinatal mortality and morbidity which can be directly related to hyperglycemia and vasculopathy in the mother, although meticulous glycemic control reduces risks and can lead to successful pregnancy outcomes.Causes & Risk Factors:During Pregnancy, the placenta supplies a growing fetus with nutrients and water. The placenta also makes a variety of hormones to maintain the pregnancy. In early pregnancy, hormones can cause increased insulin secretion and decreased glucose produced by the liver, which can lead to hypoglycemia (low blood glucose levels). In later pregnancy, some of these hormones (estrogen, cortisol, and human placental lactogen) can have a blocking effect on insulin, a condition called insulin resistance.As the placenta grows, more of these hormones are produced, and insulin resistance becomes greater. Normally, the pancreas is able to make additional insulin to overcome insulin resistance, but when the production of insulin is not enough to overcome the effect of the placental hormones, gestational diabetes results or there may be worsening of pregestational diabetes.Diabetic ketoacidosis (DKA) occurs in 5-10% of pregestational diabetics during pregnancy, with high rates of both maternal (2%) and fetal mortality (10%). Fetuses that survive episodes of DKA may be at risk for abnormal long-term neurodevelopment but the risk is unknown. Women with diabetic retinopathy can experience progression of retinopathy during pregnancy, ultimately leading to blindness. Women with pre-existing nephropathy (5-10% of diabetics) should anticipate worsening of proteinuria and hypertension in the third trimester, although this is rarely permanent. However, women with severe nephropathy (proteinuria>3g/24 hours) or serum creatinine >1.5 may experience permanent progression to end stage renal disease during pregnancy.Diabetes in pregnancy can have serious consequences for the mother and the growing fetus. The severity of problems often depends on the degree of the mother's diabetic disease, especially if she has vascular (blood vessel) complications and poor blood glucose control.Diabetes that occurs in pregnancy is often listed according to White's classification:Gestational diabetes. When a mother who does not have diabetes develops a resistance to insulin because of the hormones of pregnancy.
- Non-insulin-dependent - Class A1, which can be controlled by changes in diet.
- Insulin-dependent - Class A2.
Pre-gestational diabetes. Women who already have insulin-dependent diabetes and become pregnant.
Symptoms:Women with pregestational diabetes are three to four times more likely to have a child with one or multiple birth defects compared with mothers with no diabetes, according to study results published in the American Journal of Obstetrics & Gynecology.Poorly controlled pregestational diabetes poses a number of risks to the baby. Some of them are,
- Class B - diabetes developed after age 20, have had the disease less than 10 years, no vascular complications.
- Class C - diabetes developed between age 10 and 19 or have had the disease for 10-19 years, no vascular complications.
- Class D - diabetes developed before age 10, have had the disease more than 20 years, vascular complications are present.
- Class F - diabetic women with kidney disease especially nephropathy.
- Class R - diabetic women with retinopathy (retinal damage).
- Class T - diabetic women who have undergone kidney transplant.
- Class H - diabetic women with coronary artery or other heart disease.
Diagnosis:Women with diabetes before pregnancy (pregestational diabetes) have already been diagnosed. Depending on the severity of their disease, they may need continued care by their medical physicians along with their Obstetrician.Nearly all non-diabetic pregnant women are screened for gestational diabetes between 24 and 28 weeks of pregnancy. In addition to a complete medical history and physical examination, a glucose screening test is given, which involves drinking a special glucose drink followed by measurement of glucose levels after a one-hour interval.If this test shows an increased blood glucose level, a three-hour glucose tolerance test will be performed.If results of the second test are in the abnormal range, gestational diabetes is diagnosed.Special fetal testing and monitoring may be needed for pregestational diabetics, especially those who are taking insulin (because of the increased risks for stillbirth). These tests can include the following:
- Birth defects.
- Premature birth.
- Severe cases can causes other problems in the mother and poor growth and premature birth in the baby.
- Fetal movement counting. Counting the number of movements or kicks in a certain period of time, and watching for a change in activity.
- Ultrasound. A diagnostic imaging technique which uses high-frequency sound waves and a computer to create images of blood vessels, tissues, and organs. Ultrasounds are used to view internal organs as they function, and to assess blood flow through various vessels.
- Non-stress testing. A measurement of the fetal heart rate in response to the fetus' movements.
- Biophysical profile. A test that uses the non-stress test and ultrasound to examine fetal movements, heart rate, and amniotic fluid amounts.
- Doppler flow studies. A type of ultrasound which uses sound waves to measure blood flow.
The management of pregestational diabetes requires tight metabolic control to reduce maternal and perinatal morbidity and mortality. It has been suggested that type I diabetes is a disorder characterized by insulin deficiency and type II diabetes is characterized by insulin resistance; however, it may be hypothesized that a difference in insulin requirements should emerge throughout pregnancy to reflect the dissimilarities in these two metabolic disturbances.The risks associated with pregestational diabetes can be minimized through:
NOTE: The above information is for processing purpose. The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition.DISCLAIMER: This information should not substitute for seeking responsible, professional medical care.
- Preconception counseling.
- Optimal diabetic control before, during and after the pregnancy.
- Careful management by a Diabetes Management Team.
- Prompt diagnosis and treatment of both trivial and serious complications of pregnancy.
- Careful timing and suitable method of delivery.
- Presence of a Pediatrician with experience in the health management of infants of mothers with diabetes.
- Availability of a Neonatal intensive care nursery.