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Pregnancy journey

Gestational diabetes 

Mum pregnant and sonGestational diabetes (GDM) is a condition which develops during pregnancy and leads to high levels of glucose in the blood. Glucose comes from carbohydrates for example bread, rice, pasta, cereals and potatoes. Insulin is a hormone that acts like a key to unlock cells to allow glucose to enter. Insulin helps to lower blood glucose levels and keep them in the normal range. During pregnancy your body needs more insulin than usual. This is because the placenta releases hormones which makes your body more resistant to insulin. This is not a problem for most women however in some women they are not able to produce enough insulin to overcome this resistance and therefore blood glucose levels rise to above normal levels.

More information on GDM can be found on the Diabetes UK website , where you can also download or order a free gestational diabetes guide or access here.

Are you at risk?

  • Have you had gestational diabetes before?
  • Do you have a BMI above 30 kg/m2?
  • Have you had a large baby weighing 4.5 kg or more?
  • Do you have a family history of diabetes (close relative with diabetes - parent, brother or sister)?
  • Are you from an ethnic background with a high prevalence of diabetes?

If you fall into one of the above categories, you will be offered a glucose tolerance test. This involves attending for an appointment, this may be in a hospital setting or at one of the midwifery clinics at a local health centre, approximately between 24 - 28 weeks gestation. If you have had gestational diabetes before you may choose to monitor your blood glucose from early pregnancy so referring yourself early to your maternity team is recommended.

What are the possible complications?

Gestational causes test Your midwife, doctors, nurses and dietitians will work with you and set you targets for your blood glucose levels. Monitoring your levels correctly and meeting your targets will reduce the risk of complications and increase your chances of a healthy pregnancy. But if your gestational diabetes isn’t managed properly, it can put you at an increased risk of developing complications.

Continuous high blood glucose levels can lead to:

  • Needing to have your labour induced.
  • Having a caesarean section.
  • Having a larger than normal baby.
  • Your newborn having low blood glucose levels (neonatal hypoglycaemia).
  • Perinatal death – your baby dying at around the time of the birth.
  • Your baby having a higher risk of being overweight or obese and/or developing Type 2 diabetes in later life. As your child grows, managing their weight, eating healthily and being physically active will reduce this risk.

What happens if you are diagnosed with GDM?

Pregnant exercise If you are diagnosed with GDM, you will be offered an appointment to see one of the Diabetes Team to be shown how to monitor your blood glucose. You will also be given advice on diet and activity to help you control your blood glucose readings.

You are still able to safely exercise during pregnancy. Regular exercise is important in helping keep your blood glucose levels within the targets, for example walking for 30 minutes after a meal. Exercise will also help in preventing excessive weight gain.

Moderate intensity activity will not harm your baby. At least 30 minutes per day of moderate intensity activity is recommended. Try to avoid sitting for long periods of time, and try to build exercise into your daily life, such as taking the stairs instead of the lift. Recreational exercise such as swimming or brisk walking and strength conditioning exercise is safe and beneficial. The aim is to stay fit, rather than to reach peak fitness.

If you have not exercised routinely aim to begin with no more than 15 minutes of continuous exercise, three times per week, increasing gradually to 30 minutes per day. If you have exercised regularly before pregnancy, you should be able to continue with no adverse effects.

Weight loss

Weight loss is not recommended during pregnancy. However, making small changes to your diet and increasing your activity levels whilst you are pregnant to help manage your blood glucose levels can also help to avoid too much weight gain during pregnancy.

What if you blood glucose levels are not controlled with diet and activity?

Some women do need to take medication to help them control their blood glucose. This may be a tablet, or some may go on to need insulin injections. Your diabetes team will be able to advise you about any medication you may need to take. Your team will keep in regular contact with you to discuss you blood glucose readings and help you adjust any treatment you may need.

You may be offered more scans to check on the growth of your baby.

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Your baby is now officially an embryo and is about the size of a poppy seed.

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Your baby is now the size of a kidney bean and weighs 1g. 

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Welcome to the second trimester!

Your baby is about the size of a small lime and weighs approximately 14g.

You have hopefully seen your midwife for your 'booking in' appointment, if you have not yet seen a midwife please make an appointment quickly, so you can have all of your choices about screening tests explained and offered to you.

Please visit for more information. You can also link to the 'Pregnancy Journey' area here.  


Your baby is about the size of an avocado and weighs approximately 100g. 

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Your baby has grown in length and is now the length of a small banana and weighs approximately 300g. Around this time you will be offered your '20 week' scan, also known as the 'anatomy' or 'anomaly' scan.Click here for more information about screening. 

This is a also a good time to talk and sing to your bump as your baby can now hear sounds. This is great way for you and your partner/family to bond with your baby.

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Your baby has grown again to the approximate length of an ear of sweetcorn and weighs about 600g. 

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Welcome to the third trimester!

Your baby is now approximately the weight of an aubergine; about 1kg and approximately 37cm in length. 

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Your baby now weighs approximately the same as a coconut; around 1.5kg. 

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Your baby is now around the same size as a lettuce, approximately 47cm long and weighs around 2.6kg. 

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2019-07-03 (9)

Your baby is now the weight of a small watermelon which is approximately 3.3kg and around 50cm in length. 

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