ASDA Health Matters

Gestational diabetes

When you eat starchy foods (like bread, pasta, chapattis, potatoes, yam, noodles, rice and cereals) or sweet, sugary foods, the food is digested and broken down into glucose (a type of sugar). The glucose then travels round the body in the blood, until a hormone called insulin helps it to be used as fuel for the body.

Diabetes mellitus, more usually called diabetes, is a condition in which the amount of glucose in the blood is too high. This can happen for two reasons - either there isn't enough insulin or the insulin doesn't work properly. In both cases, the glucose can't be used as fuel and stays in the blood, leading to serious health problems.

Gestational diabetes simply means diabetes which is first recognised in pregnancy. During pregnancy, hormones stop insulin from working as well as usual, in order to make sure there's enough glucose for your baby. Most women produce two or three times more insulin to cope with these changes but, for some women, the body can't keep up with the demand.

Gestational diabetes usually begins in the second half of pregnancy, and goes away after the baby is born. If it doesn't go away after you've given birth, it's possible that you already had diabetes and that it was picked up during your pregnancy.

Am I at risk?

It's thought that gestational diabetes affects between 3-5% of pregnancies. Any woman can develop diabetes during pregnancy but certain groups of women are at an increased risk. These include women who:

• are overweight, particularly those who have a BMI above 30 at the beginning of pregnancy
• have already had a big baby, weighing 4.5kg (10lb) or more
• have had gestational diabetes before
• have a mother, father or siblings with diabetes
• have South Asian, black Caribbean or Middle Eastern family origins.

How will I know if I have it?

Your midwife will assess your risk of gestational diabetes during your first appointment (your booking appointment). If you have any of the risk factors mentioned above she will suggest that you have a test called a Glucose Tolerance Test (GTT) or Oral Glucose Tolerance Test (OGTT). If you've had diabetes in a previous pregnancy you will be offered this test at 16-18 weeks and again at 28 weeks if the first result is normal. If you have not had diabetes in a previous pregnancy but have any of the other risk factors you will be offered the test at 24-28 weeks. The test isn't done earlier because the hormonal changes affecting insulin levels don't occur until the second and third trimesters.

Your midwife will explain to you how the test is done. You usually need to fast overnight and have a blood test before breakfast. You then take a measured amount of glucose (sugar) followed by another blood test two hours later. The results show how high your sugar levels are after fasting and how your body copes with the extra sugar.

Even if you don't have any of the risk factors your midwife will still monitor you for gestational diabetes. When you see your midwife during your pregnancy she will ask you to bring a urine sample with you, which will be checked for extra sugar. A small amount can be normal in pregnancy but if you have a large amount, or continue to have sugar in your urine at other appointments, then you may be booked in for an OGTT.

How is it treated?

If the results of the OGTT show that you have developed gestational diabetes then you will be monitored closely during your pregnancy. You may be referred to a specialist diabetes midwife or doctor who will advise you how to control your blood sugar level. They'll teach you how to monitor your sugar levels and give you a blood sugar target to meet. For most women, just adapting their diet and doing moderate exercise will help. Some women who are particularly overweight may be helped to lose weight safely. If this isn't enough and your sugar levels continue to be poorly controlled you may need medication.

Will my baby be at risk?

Serious complications can occur if diabetes is undiagnosed or if sugar levels aren't well controlled. The baby can grow very large (macrosomia), which can lead to birth trauma for both the mother and the baby and increases the chances of needing an induction of labour and/or a caesarean section.

After the birth the baby can have trouble regulating her own blood sugar levels and her health can be affected later by problems such as obesity or diabetes. Unfortunately, the baby's life can also be at risk. For these reasons, if you have diabetes before pregnancy or develop it during pregnancy, it is really important that you attend all your check-ups and maintain your sugar levels as best you can to your given targets. If you are finding this difficult then ask your midwife or doctor to help you.

Where can I find out more?

For more information on gestational diabetes, visit Diabetes UK. If you are concerned about diabetes in your own pregnancy speak to your midwife or call a Tommy's midwife on 0870 777 30 60 or perhaps even visit their website www.tommys.org .

We also have live podcasts with our nutritionist here at Asda on diabetes and healthy eating during pregnancy. To listen to these simply click on the relevant links or visit the podcast section of our website.