Gestational Diabetes (GD), one of the most common medical complications of pregnancy, significantly
impacts mother and the child's health. About 5% of all the pregnant women are affected by gestational diabetes.
Historically, prior to the discovery of insulin in 1921, it was considered as a fatal condition. Although, it
existed from many decades, the term "Gestational Diabetes" was coined for this condition only in 1950s.
Following this, in 1960s, O'Sullivan found that the degree of glucose intolerance during pregnancy was
linked to developing Diabetes after pregnancy.
What is Gestational Diabetes?
Gestational Diabetes, commonly referred as diabetes during pregnancy, is a complication wherein a women develops glucose
intolerance or elevation in the blood glucose level. Mostly it resolves postpartum but, eventually some women
suffering from Gestational Diabetes become prone to type 2 diabetes. The development of insulin resistance or insufficient insulin
(hormone which controls blood glucose levels) in the body due to its higher needs during gestation primes this
form of diabetes, and can occur at any stage of pregnancy.
Pathophysiology of Gestational Diabetes
A number of maternal metabolic changes occur throughout gestation to optimize the transfer of nutrients to
fetus. These alterations to the metabolism result in high requirements of insulin and also, affects the secretion
of other hormones. Gestational Diabetes is multifactorial, including development of insulin resistance, insufficient production of
insulin by pancreas and alteration in growth hormones.
Factors like secretion of hormones and substances by the placenta, and sometimes obesity triggers the
maternal tissues to become insensitive to insulin during pregnancy. Insulin resistance starts to develop
in the beginning of mid-pregnancy and progresses during third trimester.
In an attempt to overcome this insulin resistance, the women's pancreas starts to secrete insulin in higher
amounts. Subsequently when the pancreatic cells are unable to secrete enough amount of insulin to meet
the daily needs or to compensate the insulin resistance, it results in raised blood glucose level i.e. hyperglycemia.
Variations in estrogen, progesterone, and cortisol secretion during pregnancy also changes the
glucose-insulin balance.
Different Risk Factors for Gestational Diabetes?
Common risk factors associated with Gestational Diabetes are
- Being Overweight
- Older maternal age
- Family History of Diabetes
- History of Gestational Diabetes
- Polycystic ovary syndrome (PCOS)
- Certain ethnic races like Asian,African, and Hispanic.
Other risk factors are
- Hypertension
- Recurrent abortions
- History of unexplained stillbirths
Gestational Diabetes Affecting Mother
Apart from causing adverse pregnancy outcomes like macrosomia (newborn with higher weight than average),
increased chances of caesarean section fetal hyperinsulinaemia, women having Gestational Diabetes also have significant risks
of developing type 2 diabetes later in their lives. Increased incidences of hypertensive disorders like gestational
hypertension, pre-eclampsia (usually high blood pressure) and eclampsia (seizures due to high blood pressure)
are also observed commonly. Gestational Diabetes may as well lead to metabolic syndrome, cardiovascular disease (CVD and
increase risks of preterm labor.
Gestational Diabetes Affecting Child
Excessive fetal growth which can cause birth trauma, shoulder dystocia (condition where baby's shoulder
becomes stuck during labor), and neonatal hypoglycemia are some associated complications. Other conditions
arising due to Gestational Diabetes which occurs commonly in infants are hyperbilirubinemia, hypocalcemia, erythema and
respiratory distress syndrome. Long-term effects like metabolic syndrome or type 2 diabetes in offspring are
also not uncommon. Obesity can also be observed as a long-term consequence of gestational diabetes.
Signs and Symptoms of Gestational Diabetes
Diabetes during pregnancy sometimes may not have any
noticeable signs and symptoms or it can be very subtle, easily mistaken to be side effects of pregnancy
However common signs include
- Feeling thirsty
- Being tired
- Dry mouth
These symptoms can be similar to those of other forms of diabetes and are easy to miss, making
screening tests important tool for diagnosis.
Managing Gestational Diabetes
Managing Gestational Diabetes tends to decrease the risk of adverse pregnancy outcomes and the crux of its management
lies in glycemic control. One can efficiently adhere to their blood sugar goals by changing their lifestyle,
which may involve daily exercise, nutritional therapy and blood glucose level monitoring. If changing lifestyle
fails to maintain blood glucose within normal limits then insulin therapy may be initiated by the medical practitioner.
- Exercise
Daily exercise for 30 minutes or more improves insulin sensitivity or blood glucose levels. Walking or doing
arm exercise while sitting on a chair for even 10 minutes after each meal can control post parental blood
glucose levels, helping to achieve daily blood glucose goals.
- Medical Nutritional Therapy
It is the keystone in managing diabetes during pregnancy. Quality nutrition intake becomes essential to meet
the daily demand during pregnancy which can support the maternal and fetal wellbeing while maintaining the
normal blood glucose levels. Optimal diet should focus on achieving appropriate weight gain, avoiding excess
carbohydrates and fats.
- Blood Glucose Monitoring
Monitoring levels of blood glucose is of utmost importance throughout pregnancy. Self blood glucose monitoring
should also be done; number of times the test needs to be done in a day is subjective to the patient's condition
and physician suggestion. Generally monitoring blood glucose levels after meal is preferred over pre-meals.
Insulin Therapy
It is initiated when blood glucose levels cannot be controlled after exercise and nutritional therapy. The type
and timing of insulin is selected depending upon blood glucose elevation levels. Medical practitioners also
consider body weight and gestation week to determine insulin doses.
The level returns to normal post delivery in majority of the cases. However, some women having gestational
diabetes may have elevated blood glucose level post delivery, possibly because of undiagnosed type 2 diabetes
that was present prior to pregnancy.
Gestational Diabetes is a condition which affects a significant number of pregnant women and can have long term health impact
on both mother and fetus. Having Gestational Diabetes does not mean that a woman and her child can't be healthy, as early diagnosis
and good management help to overcome its complications. It becomes important for all pregnant women to screen
for diabetes in order to minimize its risks. In conclusion, a short term care can be beneficial over long term pay off
in preventing obesity, type 2 diabetes and other conditions in the mother as well as child.