What is gestational diabetes? How does it affect pregnant women?
Pregnancy is an exciting time in a woman’s life; a time of expectations and preparations. Taking care of the mother’s health during this period is of utmost importance. In some cases, around the 24th week of pregnancy, many women are diagnosed with Gestational Diabetes, even when they have had no history of diabetes. This causes fear, apprehension and anxiety. The diagnosis of gestational diabetes does not mean that the mother will remain a diabetic after delivery, although a susceptibility to develop diabetes in the future is certainly present.
How it happens
During pregnancy, the placenta supports the baby as it grows. Placental hormones are necessary for the baby’s growth but these hormones also block the action of insulin in the mother’s body (insulin resistance). So, although the mother’s body continues to produce insulin, it is not allowed to work properly. As a result her blood glucose levels start rising. Gestational diabetes develops when the mother’s blood glucose levels rise above normal, causing hyperglycaemia.
Gestational diabetes occurs at a late stage in pregnancy when the baby has already formed but is still growing. While the baby may not have developmental birth defects —as seen in cases where the mothers had uncontrolled diabetes prior to pregnancy — it might be harmed if the condition is not treated. Rising blood sugar levels in the mother’s body send the pancreas into overdrive to produce more insulin but this does not reduce the blood glucose due to increasing insulin resistance. The insulin cannot cross the placenta but the extra glucose can easily enter the baby’s circulation through the placenta. As a result, the baby’s blood glucose levels also start rising, sending the developing pancreas into overdrive to produce extra insulin to control them. As the baby receives more glucose — more energy than it normally needs for growth — the excess is stored as fat in the body, leading to ‘macrosomia’ or ‘fat baby’.
Babies with macrosomia face their share of problems. Their large size can cause a difficult childbirth. Normal delivery may even damage the baby’s shoulder while passing through the birth passage. High levels of insulin in the blood may lead to very low blood glucose levels and severe respiratory distress at birth. Also, such babies are at an increased risk of obesity and have a higher risk of developing Type 2 diabetes in the future.
What to do
Treatment for gestational diabetes should start as soon as the mother is diagnosed. A good treatment regimen aims at keeping the blood glucose at normal levels throughout the pregnancy. It starts with special customised meal plans as well as scheduled physical activity. The blood glucose levels need to be monitored on a daily basis and insulin injections need to be taken if dietary and lifestyle measures are not able to normalise the blood sugar level. During pregnancy, doctors may prescribe insulin injections because all oral tablets cross the placenta and can harm the baby but insulin does not cross the placental barrier and, therefore, is safe.
Gestational diabetes usually goes away after pregnancy but in some cases it may return in future pregnancies too. In fact, in a small section of women, it may unmask Type 1 or Type 2 diabetes. Such women may need to continue their treatment regimen even after pregnancy. As gestational diabetes and Type 2 diabetes both are linked to insulin resistance, it is important to continue with basic dietary and lifestyle measures, especially in overweight women.