Pregestational diabetes is a condition where an individual has type 1 or type 2 diabetes before becoming pregnant, distinguishing it from gestational diabetes that develops during pregnancy and typically resolves after childbirth. Ongoing management throughout pregnancy is required to reduce potential risks for both the pregnant individual and the fetus. With proper guidance, individuals with pregestational diabetes can achieve healthy pregnancies and deliver healthy babies.
What is Pregestational Diabetes?
Pregestational diabetes includes both Type 1 (T1DM) and Type 2 (T2DM) diabetes. T1DM is an autoimmune condition where the body attacks insulin-producing cells in the pancreas, requiring daily insulin. T2DM, the more common type, involves the body’s inability to produce or effectively use insulin.
This condition affects 1% to 2% of all pregnancies in the United States, and this number has been rising. Management involves monitoring blood sugar levels, following a balanced diet, engaging in regular physical activity, and sometimes using medications. The severity of pregestational diabetes can be categorized into classes based on age at diagnosis and presence of complications, which guides medical management.
Planning for Pregnancy with Diabetes
Planning for pregnancy with pregestational diabetes significantly influences maternal and fetal health outcomes. Achieving optimal blood sugar control before conception is a primary goal, with an ideal A1C target below 6.5%. Maintaining morning glucose levels between 80-130 mg/dL and post-meal levels below 150 mg/dL is also recommended. Any reduction towards the target helps minimize risks for the baby.
Reviewing and adjusting medications is another important aspect of preconception planning. Insulin is the preferred pharmacologic treatment for all individuals with pregestational diabetes during pregnancy because it does not cross the placenta. Oral medications like glyburide and metformin, though historically used, are generally not recommended during pregnancy as they cross the placenta and may increase risks like neonatal hypoglycemia and macrosomia.
Pre-conception counseling with a multidisciplinary healthcare team, including an endocrinologist and obstetrician, is highly recommended. This counseling addresses potential pregnancy complications, lifestyle modifications, and evaluation for baseline complications such as hypertension and kidney issues. Effective contraception should be used until glycemic targets are consistently achieved, ensuring the safest possible start to pregnancy.
Managing Diabetes Throughout Pregnancy
Diabetes management throughout pregnancy requires a continuous and adjusted approach to blood glucose control. Regular self-monitoring of blood glucose is fundamental, often requiring checks upon waking, before meals, and one to two hours after meals. This frequent monitoring helps individuals and their healthcare teams make timely adjustments to insulin or medication regimens, as insulin needs can fluctuate significantly, particularly increasing in the second and third trimesters due to rising insulin resistance.
Continuous glucose monitoring (CGM) systems are a valuable tool, providing real-time glucose levels and trends. CGM aids in making precise adjustments to insulin doses and overall diabetes management, potentially improving glycemic control and reducing the risk of complications for both mother and baby.
Dietary adjustments are a cornerstone of managing diabetes in pregnancy, focusing on balanced nutrition. This involves spreading carbohydrate intake across three meals and two to three snacks, emphasizing whole grains, lean proteins, healthy fats, and plenty of fruits and vegetables, while limiting sugary foods and beverages. A registered dietitian can provide personalized meal plans and guidance.
Regular physical activity also contributes to blood sugar control by improving insulin sensitivity. Moderate exercise, such as walking, swimming, or low-impact aerobics, for at least 30 minutes on most days of the week is recommended, provided there are no medical contraindications. Individuals should consult their healthcare provider to determine safe and appropriate exercise routines.
Frequent prenatal visits are a standard component of care for individuals with pregestational diabetes. These visits allow for close monitoring of the pregnant individual’s health and the baby’s development. Specific tests, such as detailed fetal ultrasounds, are performed to monitor fetal growth and screen for birth defects, especially around 18-20 weeks. Non-stress tests (NSTs), which monitor the baby’s heart rate in response to movement, may also be conducted regularly, often starting in the third trimester, to assess fetal well-being.
How Pregestational Diabetes Can Affect Mother and Baby
Pregestational diabetes can lead to several health implications for both the pregnant individual and the baby, particularly if blood sugar levels are not well-managed. For the pregnant individual, there is an increased risk of preeclampsia, a condition characterized by high blood pressure and organ dysfunction, often developing in the second half of pregnancy. Preeclampsia can lead to premature birth and severe health issues during labor and delivery. Pregestational diabetes also increases the likelihood of needing a Cesarean section (C-section) due to complications like a large baby.
For the baby, poorly controlled pregestational diabetes can result in macrosomia, meaning the baby grows significantly larger than average. This increased size can lead to difficulties during vaginal delivery, including shoulder dystocia where the baby’s shoulders get stuck in the birth canal. Babies of mothers with diabetes are also at a higher risk of hypoglycemia (low blood sugar) shortly after birth, as their bodies have become accustomed to high glucose levels in the womb and continue to produce excess insulin after delivery.
Furthermore, pregestational diabetes increases the risk of birth defects, particularly affecting the heart, central nervous system, and skeletal system. The risk of these malformations is directly related to the degree of maternal hyperglycemia, especially during the first trimester when major organs are forming. Babies may also experience respiratory distress syndrome (RDS), a breathing problem due to immature lungs, and an increased risk of stillbirth, especially with large or small for gestational age fetuses. These risks are significantly reduced when blood sugar levels are tightly managed before and throughout pregnancy.
Care After Delivery
Following delivery, immediate care for the mother with pregestational diabetes involves significant adjustments to insulin doses. Insulin requirements decrease rapidly after the placenta is delivered, often necessitating a significant reduction in pre-pregnancy doses. Close monitoring of blood glucose levels is maintained to prevent hypoglycemia, which can occur due to the sudden drop in insulin needs.
For the newborn, monitoring for hypoglycemia is a priority, typically starting within the first hour or two after birth. Early feeding, whether breastfeeding or formula, is encouraged to help stabilize the baby’s blood glucose levels. In cases of persistent low blood sugar, glucose gel or intravenous glucose may be administered. The baby’s blood sugar levels are checked regularly until they are consistently normal, which may take a few days.
Breastfeeding is generally encouraged for mothers with diabetes, as it offers health benefits for both mother and baby, potentially reducing the mother’s risk of developing type 2 diabetes and lowering the baby’s risk of obesity and diabetes. Long-term follow-up for the mother includes screening for diabetes 6 to 13 weeks postpartum and annually thereafter. For the baby, long-term follow-up may involve monitoring for future diabetes complications or the development of obesity.