Many women who are diagnosed with gestational diabetes ask themselves what they did to cause their diagnosis.
The fact is, there is no single cause, and genetic factors such as age, ethnic background and family history can all increase your risk. In Australia, gestational diabetes is the fastest growing diabetes with one in every seven women diagnosed during pregnancy.
Women planning a pregnancy, in the early stages of pregnancy and between pregnancies can reduce their risk of gestational diabetes by following a healthy lifestyle. This includes maintaining a healthy weight, eating a balanced diet and keeping active.
What is gestational diabetes?
Gestational diabetes occurs during pregnancy when the hormones produced by the placenta block the action of a women's insulin in regulating blood sugar levels. Irregular blood sugar levels can lead to pregnancy complications including early labour, bigger babies and high blood pressure.
Once the baby is born, Gestational diabetes usually goes away. However, research shows women have a 30-69% risk of a gestational diabetes reoccurring in future pregnancies and up to 70% risk of developing type 2 diabetes within the next 10-20 years.
There is good news. In most cases, gestational diabetes can be managed to ensure a healthy mum and baby.
What do we know about the causes?
There are several factors[i] that contribute to a diagnosis of gestational diabetes, including:
Research has shown that women over the age of 40 are at a higher risk of gestational diabetes than younger expectant mothers.
It is now understood that ethnicity has an impact on the risk of being diagnosed with gestational diabetes. Specific ethnicities at risk include Asian, Indian Subcontinent, Aboriginal, Torres Strait Islander, Pacific Islander, Maori, Middle Eastern or non-white African backgrounds.
A family history of type 2 diabetes or a first-degree relative i.e., mother or sister who has had gestational diabetes also increases your risk.
Women who are above a healthy weight range and/or gain weight rapidly in the first 20 weeks of pregnancy are at higher risk of developing gestational diabetes. The good news is that following a healthy lifestyle including regular physical activity and a good diet can significantly reduce your risk.
A previous diagnosis
If you have had gestational diabetes in an earlier pregnancy or elevated blood sugar levels in the past, studies suggest you are 30-69% more likely to be diagnosed in a future pregnancy.
Some types of medications including antipsychotic or steroid medications can increase your risk of gestational diabetes. If you have any questions about the long-term effects of any medications you are currently taking, ensure you consult with your GP or Pharmacist.
There is an increased risk in developing gestational diabetes for women with polycystic ovarian syndrome (PCOS). PCOS is one of the most common hormonal problems in women during their reproductive years, and in most cases are undiagnosed.
How is gestational diabetes diagnosed?
Gestational diabetes is usually tested for between 24 and 28 weeks of falling pregnant, as the symptoms are not always visible. In Australia, it is diagnosed using a fasting blood test and oral glucose tolerance test (OGTT). You will need to fast overnight (not eat anything) before having this test. Many women choose to go for the test in the morning after fasting overnight and skipping breakfast.
Following the fasting test, you will drink a pure glucose drink and wait to be tested again in one hour and then two hours during which time you are unable to eat or drink anything except water.
Your doctor will be able to give you your test results either later the same day or within 48 hours. If your blood sugar level is above the normal range at your fasting, one or two-hour test, then you have gestational diabetes. You doctor will be able to explain the diagnostic criteria and how it compares to your blood test result.
Managing Your Diagnosis
There are many steps you can take to help manage your blood glucose levels. Your health professional team who specialise in diabetes management will be able to guide you including diabetes educators, dietitians, pharmacists, your GP and endocrinologists.
In most cases, management of gestational diabetes involves daily blood glucose monitoring, lifestyle changes around diet and exercise and sometimes medication including metformin or insulin.
Blood monitoring – Blood sugar monitoring is a very important part of managing gestational diabetes. Awareness of your blood sugar levels will help you to understand what affects them, including food, exercise, medication and stress. It also means you can make adjustments to ensure your management plan is working to keep your blood sugars within the target range.
To check your blood glucose levels, you will need specific diabetes testing equipment including a blood glucose meter, a finger pricking device called a lancet device with lancets and blood glucose testing strips.
Your diabetes educator or doctor will spend time teaching you how to take your blood sugar levels and what your target blood sugar levels should be.
Healthy eating is essential to help keep your blood sugar levels within the target range, to maintain good nutrition for you and your baby during pregnancy and to keep within a healthy weight range. Eating well when have gestational diabetes means choosing the right type and amount of carbohydrate foods, and eating a variety of nutrient-dense foods like fruit and vegetables and limiting foods high in saturated fats. There are many resources available including recipe books, healthy shopping guides and portion plates to help you with following a healthy eating plan.
Regular, moderate-intensity exercise is beneficial for managing gestational diabetes unless you have been told not to exercise by your healthcare team. Regular exercise helps reduce blood sugar levels so you are more likely to keep your levels within the safe range. There are many pregnancy-safe activities you can try to help keep fit and healthy for birth, and when carrying around a newborn.
In some circumstances, your doctor or diabetes educator may talk to you about starting medication if blood sugar levels are not reaching target range from diet and exercise alone. In this situation, women with gestational diabetes may be prescribed Metformin, an oral medication, to accompany their healthy eating and exercise plan. Metformin works by lowering the amount of sugar produced in the liver and increasing the sensitivity of cells to insulin.
In 10-20% of cases, insulin will be required during pregnancy to keep blood sugar levels within a healthy range. This requires injections usually administered through an insulin injection pen device, which is easy to use and safe for both you and your baby. Injection aids are also available if you experience pain or bruising from injecting. Keep all of your equipment in one place and store in a diabetes case. It is necessary to keep insulin safe and at the recommended temperature. There are a range of cooling cases available using technology to provide safe cool temperatures outside the home.
Your diabetes educator or doctor will support you to manage your blood sugar levels using insulin.
The good news is that you can access subsidised products to help you manage your diabetes by registering with The National Diabetes Services Scheme (NDSS). The NDSS is an Australian Government initiative administered by Diabetes Australia. Registration with the NDSS is free and open to everyone in Australia with a Medicare card, diagnosed with diabetes.
There is not one factor alone that causes gestational diabetes. We do know that age, ethnic background and a family history of gestational diabetes can make you more predisposed. If you have had gestational diabetes in a previous pregnancy, your risk in subsequent pregnancies is increased. Monitoring your blood sugars, maintaining a healthy weight range, eating a balanced diet and exercising regularly are vital in the management of gestational diabetes. If you have been prescribed metformin or insulin, it is important to follow the instructions provided from your health care professional. By registering with the NDSS, you will have access to subsidised products to assist with managing your diabetes.
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