Gestational Diabetes

Being told you have gestational diabetes can bring up a whole mixture of feelings. You might be worried about your baby, confused about what the diagnosis actually means, or wondering whether you've somehow caused it. Let's start with the important bit: gestational diabetes is common, it is manageable, and having it does not mean you have done anything wrong. Most people with gestational diabetes go on to have healthy pregnancies and healthy babies. Good management can reduce the risks associated with the condition.

What is Gestational Diabetes?

Gestational diabetes is diabetes that develops during pregnancy. During pregnancy, your body needs to produce more insulin, the hormone that helps control the amount of glucose in your blood. Pregnancy hormones can make it harder for insulin to work effectively, and sometimes your body cannot produce enough insulin to meet the increased demand. This causes your blood glucose levels to rise.

Gestational diabetes can develop at any point in pregnancy, although it is more common in the second or third trimester. It usually goes away after your baby is born. And despite what you might hear, gestational diabetes isn't simply a consequence of eating too much sugar during pregnancy. It is primarily about the way pregnancy changes how your body responds to insulin.

Who is more likely to develop gestational diabetes?

Anyone can develop gestational diabetes, but some people have a higher chance. Risk factors include:

being over 40
having a BMI over 30
having previously had a baby weighing 4.5kg (10lb) or more
having had gestational diabetes in a previous pregnancy
having a parent, brother or sister with diabetes

If you've had gestational diabetes before, you are also more likely to develop it in a future pregnancy. Having one or more risk factors does not mean you will definitely develop gestational diabetes. And not having any of these risk factors doesn't mean you cannot develop it.

How is Gestational Diabetes Diagnosed?

If you're considered to have a higher chance of developing gestational diabetes, you'll usually be offered an oral glucose tolerance test (OGTT) between 24 and 28 weeks of pregnancy. This involves drinking a glucose drink and having blood tests to see how your body processes the glucose. If you've had gestational diabetes in a previous pregnancy, you may be offered testing earlier in pregnancy, with another test later on if the initial result is normal. Your maternity team will explain what your local testing process involves.

What Happens if I'm Diagnosed?

If you're diagnosed with gestational diabetes, you'll usually be offered support from a specialist diabetes and maternity team. You'll normally be shown how to monitor your blood glucose levels at home using a finger-prick testing device. You'll also be given advice about food and physical activity, and you'll have additional monitoring during your pregnancy.

For some people, changes to food and activity are enough to keep blood glucose within the recommended range. For others, medication is needed. This may include tablets or insulin. Needing medication doesn't mean you've failed at managing your gestational diabetes. Sometimes your body simply needs more help to keep blood glucose at a safe level during pregnancy.

Does Gestational Diabetes Mean I need to go on a Strict Diet?

Not necessarily. You'll usually be given advice about eating a healthy, balanced diet and choosing foods that have a lower impact on blood glucose. You may also be encouraged to stay active in ways that are appropriate for your pregnancy and your individual circumstances. This isn't about trying to eat as little as possible or avoiding carbohydrates altogether. Pregnancy is not the time for crash diets, guilt or trying to "be good". If you've been diagnosed with gestational diabetes, ask your maternity team or dietitian for advice that's appropriate for you.

Can I Still Exercise?

For most people, appropriate physical activity can be part of managing gestational diabetes. Walking, swimming and pregnancy-appropriate exercise can all be useful, and your maternity team can advise you about what is suitable for your individual circumstances. If you have already been active during pregnancy, a diagnosis of gestational diabetes doesn't automatically mean you need to stop.

As always, check with your maternity team if you're unsure what activity is appropriate for you. You can explore more about movement in pregnancy in the Relaxed Mama Library.

Why does Gestational Diabetes Matter?

Most people with gestational diabetes have healthy pregnancies and healthy babies. However, if blood glucose levels are high, there can be an increased chance of certain complications. These can include:

your baby growing larger than usual
having more amniotic fluid than usual
pre-eclampsia
premature birth
your baby having low blood glucose after birth
your baby developing jaundice
difficulties during birth
needing an induction or caesarean birth

Stillbirth is also associated with gestational diabetes, although it remains rare. This list can sound frightening. It's worth remembering that these are increased risks, not inevitable outcomes. Managing blood glucose and receiving appropriate maternity care can reduce the chance of complications.

Will I Need Extra Scans?

Usually, yes. Because gestational diabetes can increase the chance of your baby growing larger than usual or there being more amniotic fluid, you may be offered additional ultrasound scans to monitor your baby's growth and wellbeing. The exact monitoring schedule will depend on your circumstances and your local maternity service. NHS guidance currently describes additional growth scans around 28, 32 and 36 weeks, with further checks from around 38 weeks. This is one of those situations where monitoring gives you information, rather than automatically determining what will happen next. If a scan suggests your baby is larger than expected, for example, you can ask what that actually means for you, how reliable the estimate is, and what your options are.

What does Gestational Diabetes Mean for Birth?

This is often the part that causes the most anxiety. You may be told that you'll need to have your baby by a particular point in pregnancy, or that induction or caesarean birth may be recommended. The timing will depend on things such as:

how well your blood glucose is controlled
whether you are taking medication
your baby's growth
the amount of amniotic fluid
your health and your baby's health
your individual circumstances

NHS guidance says that, when there are no other concerns, birth is usually recommended by around 40+6 weeks for someone with gestational diabetes. Earlier birth may be recommended if there are concerns about your health, your baby's health or blood glucose control. This doesn't mean that a diagnosis automatically equals induction.

If induction is recommended, you can ask: "Can you explain why you're recommending this for me?" "What are the benefits of doing it now?" "What are the risks of waiting?" "What are my alternatives?" "What would happen if I chose to wait?" These are useful questions whenever a recommendation about your pregnancy or birth is made. You can read more about induction of labour and your birth options elsewhere in the library.

What Happens During Labour?

Your maternity team will usually monitor your blood glucose during labour and birth. You may need insulin or glucose through a drip if your blood glucose needs additional management. Your baby's blood glucose will also usually be checked after birth because babies born following a pregnancy affected by gestational diabetes have an increased chance of low blood glucose. This doesn't mean your baby has diabetes. Your baby may simply need some additional monitoring and feeding support while their blood glucose settles after birth.

What Happens After my Baby is Born?

For most people, gestational diabetes goes away after birth and medication used during pregnancy is usually stopped. Your baby's blood glucose will be checked after birth, and you will usually be encouraged to feed your baby soon after birth and regularly afterwards.

You'll also need follow-up for yourself. The NHS recommends a blood test 6 to 13 weeks after giving birth to check whether your blood glucose has returned to normal. If the result is normal, you'll usually be offered or advised to have diabetes testing every year because having gestational diabetes increases your future risk of developing type 2 diabetes. Having gestational diabetes also increases the chance of developing it again in a future pregnancy.

Does Gestational Diabetes Mean I Will Get Type 2 Diabetes?

No. But having gestational diabetes does mean that your future risk of developing type 2 diabetes is higher than it would otherwise be.

This is why your postnatal follow-up matters, even if you're feeling completely well. There are also things you can do over time to reduce your risk, including staying active and eating a balanced diet.

A Diagnosis isn't a Judgement

There can be a surprising amount of guilt attached to gestational diabetes. You might find yourself thinking: "Did I eat too much sugar?"

"Should I have exercised more?" "Have I caused this?" Try not to turn your diagnosis into a moral judgement about your pregnancy.

Gestational diabetes happens because of the complex interaction between pregnancy hormones, insulin and your body's individual response to pregnancy. Your job now isn't to be perfect. It's to understand what's happening, work with your maternity team, monitor your blood glucose as advised and make informed decisions about your care.

Questions You Might Want to Ask

If you've just been diagnosed, you might find it helpful to ask:

What do my blood glucose results actually mean?
How often do I need to test my blood glucose?
What levels are you aiming for?
What support will I receive with food and exercise?
Will I see a dietitian or diabetes specialist?
Do I need medication?
Will I need additional scans?
How might gestational diabetes affect my options for birth?
When are you recommending that I give birth, and why?
What happens if I go into labour before then?
What monitoring will I and my baby have during labour?
What will happen to my baby's blood glucose after birth?
When will I be tested for diabetes after pregnancy?

And if something doesn't make sense, ask them to explain it again. You don't need to become a diabetes expert overnight.

The Important Bits to Remember

Gestational diabetes is high blood glucose that develops during pregnancy.
It is common and usually goes away after birth.
It is not your fault.
Most people with gestational diabetes have healthy pregnancies and healthy babies.
Managing blood glucose can reduce the risks associated with the condition.
Treatment might involve changes to food and activity, medication, or both.
You may be offered additional monitoring during pregnancy.
A diagnosis does not automatically mean you will need an induction or caesarean.
You'll need follow-up after birth because gestational diabetes increases your future risk of type 2 diabetes.
You are allowed to ask questions about any recommendations made about your pregnancy or birth.

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Movement in Pregnancy
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Your Birth Preferences
Start thinking about what matters to you for your birth, including your preferences around monitoring, pain relief and interventions.