Phil Kieran: I'm worried about getting gestational diabetes again

Gestational diabetes risk factors are a family history of the condition, a higher BMI, a previous baby who was born at high birth weight, those with polycystic ovarian syndrome or anyone who had GDM in a previous pregnancy

Tue, 04 Mar, 2025 - 01:00

Dr Phil Kieran

I developed gestational diabetes during my first pregnancy, which was well-managed. I'd like to have a second child, but I'm worried about developing the condition again. Is there anything I could do to reduce my risk?

Gestational diabetes mellitus, or GDM, is relatively common, occurring in 12.4% of pregnancies, according to the latest statistics. This is a condition where your body’s ability to control its sugar levels is suppressed, which in turn allows the sugar levels to rise.

To explain this, we need to understand how sugar control is supposed to work:

When we eat, carbohydrates in food are broken down into glucose and other sugars (mainly glucose, though). If our blood sugar levels get too high, we can run into difficulty as it causes our blood to become more concentrated, which makes us thirsty and makes it more difficult for specific chemical reactions to happen in the body.

Insulin pushes glucose into our muscle cells and tells our liver to switch from making glucose to storing it. If the blood sugar level gets too low, many cells in our body can use alternative fuel sources. However, nerve cells, most notably in our brain, can’t use fuel other than glucose, so they start to malfunction. This can lead to confusion or shaking.

Many hormones, like growth hormone, prolactin and progesterone, are produced at higher levels during pregnancy to help the foetus grow. These hormones, to greater or lesser extents, reduce insulin activity, increasing what we call 'insulin resistance'.

Not all women are screened for GDM, but anyone with risk factors for this condition should be tested.

These risk factors are a family history of the condition, a higher BMI, a previous baby who was born at high birth weight, those with polycystic ovarian syndrome or anyone who had GDM in a previous pregnancy.

Treatment aims to keep the blood sugars normal throughout the pregnancy.

The first step will be dietary and exercise advice. Eating a diet low in sugars reduces the strain on your insulin system to bring blood sugars down constantly.

You may also be given lifestyle advice to keep your muscle strength up and active, which can help insulin sensitivity. If this is not keeping your blood sugars within the normal range, you will be advised on specific medications, including — for some people — injecting insulin.

By following the healthy eating advice outlined above and reducing the modifiable risk factors by exercising regularly and maintaining a healthy weight, you can reduce your risk of developing GDM in subsequent pregnancies. Although it may not be possible to avoid developing GDM, becoming and staying fitter can mean it is less severe and may not require treatment.

We also know that women with GDM have a slightly increased risk of developing type 2 diabetes mellitus in later life. To reduce the risk of this happening, the same advice applies — staying a healthy weight, remaining active and eating a healthy diet. A yearly screening programme is available for those who have had GDM, usually with your GP. You can access a free consultation and blood test annually to screen for diabetes.