What is Diabetes Mellitus
Diabetes Mellitus is an endocrine disorder where the pancreas does not or insufficiently produce insulin to regulate body glucose levels. A pregnant woman with diabetes mellitus may find difficulty controlling the balance between insulin and blood glucose levels to prevent hyperglycemia or hypoglycemia because so many changes are happening to the body during pregnancy. Both hyperglycemia and hypoglycemia are dangerous during pregnancy because they are threats to normal fetal growth.
Pregnant women tend to develop insulin resistance as pregnancy progresses. This phenomenon is thought to be caused by the presence of the hormone human placental lactogen and increased levels of estrogen, progesterone, cortisol, and catecholamines during pregnancy. The rate of insulin secretions is also increased and the fasting blood sugar level is lowered. The presence of placental insulinase helps maintain a normal pregnancy by breaking down insulin thus preventing blood glucose from falling to dangerous limits, despite the increased insulin secretion that occurs. A diabetic pregnant woman must increase her insulin dosage beginning on the 24th week of her pregnancy to prevent hyperglycemia. At the same time, the continued consumption of glucose by the fetus may lead to hypoglycemia for the mother between meals; this is most likely to occur overnight. She may become ketoacidotic from the breakdown of stored fat, which is likely to occur during the 2nd and 3rd trimesters. Diabetic womeqan are at risk to develop hydramnios, an increase in the amount of amniotic fluid, thought to be caused by hyperglycemia in the fetus that causes increased urine production. Amniocentesis may be required to corret the problem but this will expose the pregnant woman to risk of infection and possible preterm labor. This corrective measure is temporary because amniotic fluid is continually reproduced. If the woman has a pre-existing kidney disease, the risk of fetal growth restriction, asphyxia, still birth and maternal pregnancy-induced hypertension increases markedly.
There is a high incidence of congenital anomaly such as caudal regression syndrome, spontaneous miscarriage and stillbirths in infants of women with diabetes mellitus.
Infants of diabetic women are five times more apt to have heart anomalies than others. Infants of women with poorly controlled diabetes tend to be large (more than 10 lbs) because the amount of insulin the fetus must produce to counteract the excessive amount of glucose the fetus' receives acts as a growth stimulant. The increased glucose adds to the fetus' subcutaneous fat deposit. A macrosomic infant is at risk to cephalopelvic disproportion, a condition that exposes the neonate to shoulder dystocia making it necessary for the mother to undergo caesarean section.
Signs and symptoms
A pregnant woman with diabetes may manifest the following symptoms: dizziness when hypoglycaemic, confusion if hyperglycaemic, thirst; glycosuria, polyuria on urinalysis; hyperglycemia on fasting blood sugar testing. The fetus that is large for gestational age is indicative of macrosomia; poor fetal heart tone variability and rate from poor tissue perfusion and hydramnios.
What to do
A diabetic woman planning to get pregnant must go to her obstetrician and get help in controlling hyperglycemia during the early weeks of pregnancy, when the tendency of congenital anomalies in the fetus is highest. A home test kit is useful to determine at the earliest time if she is pregnant so that the best insulin control program during pregnancy can be determined.