Even if you don’t have diabetes normally, you can still develop gestational diabetes during pregnancy. Here’s what it is and how it’s managed.

Gestational diabetes is a type of diabetes that develops during pregnancy, and then goes away once the pregnancy is over. You may be more familiar with type 2 diabetes, and it is similar in many ways, requiring blood sugar testing and healthy changes to your diet to keep it under control.  

What is gestational diabetes? 

If you have gestational diabetes, it means that your blood sugar (or blood glucose) levels are high, and that your body can’t produce enough insulin to keep these levels under control. 

During pregnancy, women need more insulin to help manage blood sugar levels because of the extra demands on the body that come with being pregnant. This is why women who don’t have diabetes when not pregnant can develop gestational diabetes.  

Who is at risk? 

You can develop gestational diabetes at any stage during pregnancy, and it can happen to any woman. However, you do have an increased risk if: 

• your BMI is over 30 
• you had gestational diabetes in a previous pregnancy 

• you’re of south Asian, Black, African-Caribbean, or Middle Eastern origin 
• you’ve had a baby who weighed 4.5kg (10lbs) or more at birth 
• one of your parents or siblings has diabetes 

What are the symptoms? 

Gestational diabetes doesn’t usually cause any symptoms. If you’re in one of the risk groups, you’ll be offered screening for gestational diabetes during your pregnancy and it’s here that it’s picked up.  

The screening for gestational diabetes is also known as the oral glucose tolerance test (OGTT). It takes around 2 hours and involves two blood tests. The first is a fasted blood test and the second is taken after you’ve had a sugary drink and rested for 2 hours. These results will show how your body deals with the glucose. 

You might develop some symptoms if your blood sugar gets too high, like being thirstier, needing to pee more often than usual, a dry mouth and tiredness. This doesn’t necessarily mean you’ve got gestational diabetes, as these are also common pregnancy symptoms. If you’re worried about any symptoms, it’s always best to talk to your midwife. 

What are the risks? 

If gestational diabetes is left untreated, it can lead to problems for both mum and baby. 

Some problems include: 

• your baby having a higher birth weight, which can lead to problems during delivery 
• polyhydramnios – too much amniotic fluid around the baby, which can cause premature labour or delivery problems 

• premature birth – giving birth before 37 weeks 
• pre-eclampsia – a condition where your blood pressure is too high, which can lead to further complications 
• your baby developing low blood sugar or jaundice  

How is it treated? 

Gestational diabetes can be kept under control by keeping a close eye on your blood sugar levels to make sure they don’t get too high. This means you’ll have to use a blood sugar testing kit at home, where you’ll prick your finger to test a drop of blood.  

You’ll need to change your diet and exercise habits to reduce your blood sugar levels. You’ll be given guidance by your midwife, who will arrange for you to see a dietitian if necessary. In general, you’ll be encouraged to avoid sugary foods and drinks, to eat starchy and low-glycaemic index foods like wholewheat bread and pasta instead of white versions, and to aim to eat at least 5 portions of fruit and vegetables a day. 

You’ll also be encouraged to keep active by doing regular exercise. 

If changing your diet and exercise habits don’t control your blood sugar levels after around 2 weeks, you’ll be given medication in the form of either tablets or insulin injections. 

You’ll be offered extra antenatal appointments, including extra scans to check your baby’s growth and the amount of amniotic fluid.  

Gestational diabetes goes away after giving birth, but you may be at risk of developing it in any future pregnancies, and you will be at higher risk of developing type 2 diabetes.