Gestational diabetes occurs when a female develops diabetes between weeks 24 and 28 of pregnancy. It is referred to as gestational diabetes when the female only develops the condition during pregnancy and has not been diagnosed with diabetes prior to pregnancy.
Gestational diabetes occurs in about 14% of pregnancies globally. Like other forms of diabetes, it affects the way the body uses sugar and influences insulin function, resulting in increased blood glucose levels. In most cases, women’s blood glucose levels return to normal soon after delivery. However, there is still a risk of developing type 2 diabetes and cardiovascular diseases post-pregnancy. It is crucial to diagnose and manage gestational diabetes as it impacts both the mother’s health and the unborn baby’s health, both now and in the future.
Understanding Glucose Control During Pregnancy
During pregnancy, a mother’s body undergoes various changes to adapt and support the growth of the foetus. One important change is the metabolic adaptation of insulin sensitivity. Insulin, secreted by the pancreas, is responsible for lowering blood glucose levels. Insulin sensitivity changes throughout pregnancy.
Early on, sensitivity increases, leading to greater glucose uptake and storage in fat cells to provide energy for later pregnancy stages. However, as the pregnancy progresses, hormones like oestrogen, progesterone, and leptin are released as the foetus grows, leading to insulin resistance. This breakdown of glucose stored in fat cells further raises blood glucose levels.
Gestational Diabetes Risk Factors
Several risk factors increase the likelihood of developing gestational diabetes. These factors directly or indirectly impact the functioning of beta cells in the pancreas, affecting insulin sensitivity. Let’s explore the key risk factors:
- Overweight or Obesity: Having a BMI between 25 and 30 (overweight) or 30 or higher (obesity) before or during early pregnancy increases the risk of gestational diabetes. This is often linked to a Western diet, which can overwhelm beta cells, leading to insulin resistance and elevated blood glucose levels as fatty acids are released from fat stores.
- PCOS: Women with polycystic ovary syndrome (PCOS) often have insulin resistance and subfertility. A diagnosis of PCOS before pregnancy can increase insulin resistance, raising the risk of gestational diabetes.
- Pre-existing Diabetes: Women with insulin resistance or diabetes before pregnancy are likely to develop gestational diabetes.
- Previous Gestational Diabetes: If a woman had gestational diabetes in a prior pregnancy, she is at higher risk of developing it again.
- Physical Inactivity: A lack of physical activity during pregnancy increases the likelihood of gestational diabetes.
- High Birth Weight: A previous delivery of a baby weighing more than 4.1 kg increases the risk of developing gestational diabetes in subsequent pregnancies.
Complications
Gestational diabetes can lead to several complications for both the mother and child. It can contribute to pregnancy complications such as pre-eclampsia or pre-term birth. Over half of the women with gestational diabetes develop type 2 diabetes later in life. Additionally, women with gestational diabetes are at a higher risk of cardiovascular disease, one of the leading causes of death globally due to heart attack or stroke. The child is also at risk, with an increased likelihood of developing type 2 diabetes and becoming overweight or obese during childhood.
Prevention
While it is not possible to fully prevent gestational diabetes, there are steps that can reduce the risk. Maintaining a healthy diet, limiting processed meats, refined sugars, and excessive fats, while increasing the intake of fruits, vegetables, and healthy fats, is essential. A doctor or nutritionist may recommend supplements to ensure the body receives the necessary vitamins and nutrients to support pregnancy and foetal growth. Staying active before and during pregnancy can help control weight and lower the risk of gestational diabetes. Physical activity helps burn free fatty acids and maintains insulin sensitivity, supporting normal blood glucose levels and minimising weight gain during pregnancy. Additionally, achieving a healthy weight before pregnancy can reduce the risk of obesity and type 2 diabetes later in life.