What is gestational diabetes and what are the risks?

Medically reviewed December 2021
gestational diabetes pregnancy Naytal

Short on time? Then the key things to know are:

  • Gestational Diabetes is a type of diabetes that can occur during pregnancy
  • If you fall into one of the risk categories for developing gestational diabetes you will automatically be referred for an oral glucose tolerance test (GTT) at around 28 weeks
  • There are no obvious signs and symptoms of gestational diabetes
  • This form of diabetes can often be controlled by diet and maintaining an active lifestyle
  • There is nothing you can do to prevent gestational diabetes, but maintaining a healthy and active lifestyle can help to reduce your chances of developing this particular type of diabetes


At a time when you are already probably feeling a little more anxious than you would be, to then be told that you have Gestational diabetes can throw you right off your feet.

Rest assured that if you develop gestational diabetes, you will be well cared for by a whole host of health professionals; doctors, midwives and dieticians. With this incredible care package and careful monitoring you can continue to have a perfectly safe and healthy pregnancy.

What is gestational diabetes and what causes it?

Gestational diabetes (GD) is a type of diabetes that can develop during pregnancy. Some of the hormones that women produce during pregnancy can affect the production of insulin (the hormone that helps to control sugar levels in the bloodstream), therefore, leading to too much sugar in the blood.

How common is gestational diabetes?

Gestational diabetes can affect around 18% of pregnancies and despite all the research around this topic we are still not 100% sure why some women develop gestational diabetes.

It can often be controlled by diet and light exercise but may need medication in some instances. If this type of diabetes is detected, women will need to check their blood sugar levels closely throughout the rest of their pregnancy.

Who is at risk of developing gestational diabetes?

Many women are at risk of developing gestational diabetes for numerous reasons and will be offered a Glucose Tolerance Test (GTT) at the beginning of the 3rd trimester, around 28 weeks gestation. Reasons such as:

  • Gestational diabetes in a previous pregnancy
  • Polycystic ovaries (PCOS)
  • First degree family relative who has diabetes (mother/father/sister/brother)
  • Previous baby weighing over 4.5kg (10lb+)
  • Raised BMI (over 35)
  • Black or Asian or middle eastern ethnicity

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What are the signs of gestational diabetes?

Gestational diabetes quite often doesn’t present with any symptoms and most women will only discover that they have the condition if they are screened for it.

As the classic symptoms for diabetes are feeling more tired and needing to pee more often, it is difficult to distinguish if these symptoms are down to diabetes or just normal pregnancy side effects.

Everyone is screened for glucosuria (sugar in their urine) at each routine appointment and if it is ever detected, will be referred for a glucose tolerance test (GTT). This is the only way we can diagnose gestational diabetes.

What are the risks of having gestational diabetes?

Gestational diabetes may cause problems during pregnancy, but all these risks can be avoided with close monitoring and careful planning. If the diabetes is well managed and your blood sugar levels are well controlled, you can continue with a safe and healthy pregnancy.

Cesarean vs. vaginal birth

If you develop gestational diabetes, this does not mean that you are automatically signed up for an elective caesarean section. Many women who develop GD go on to have perfectly normal pregnancies and vaginal births.

Induced labour

If the diabetes becomes difficult to control towards the end of the pregnancy, women may be offered an induction of labour prior to their due date. Gestational diabetes can sometimes be a risk factor for developing pre-eclampsia during pregnancy, so the midwives will check your blood pressure and urine at every appointment to rule this out.

Growth of your baby

If the gestational diabetes is not well managed it can occasionally cause babies to grow a bit more than at the normal rate, this is because having high blood sugar levels can cause you to produce more insulin. As this happens the baby will also produce more insulin which can cause them to grow larger than they would otherwise.

Baby’s blood sugar levels

After the baby is born, he/she may need to have their blood sugar levels monitored to ensure that they are able to maintain their own blood sugar levels satisfactorily. You will be able to breastfeed or bottle feed, whichever method you choose, but it is imperative that the baby is fed early (as soon as it is practicable) and regularly.

Does having gestational diabetes mean I am now always going to be diabetic?

Unfortunately, if you develop gestational diabetes, it can mean you are likely to develop it again in subsequent pregnancies. It can also mean that you are at higher risk of developing type 2 diabetes after birth or later on in life.

It can also mean that your child is more at risk of developing type 2 diabetes as an adult.

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How can I prevent Gestational Diabetes?

There is no way that we can prevent gestational diabetes and as previously mentioned, we still don’t know why some people develop it.

However, it is thought that maintaining a healthy and active lifestyle before and during your pregnancy can reduce your chances of developing this particular type of diabetes.

For more information head over to www.diabetes.org.uk or www.tommys.org.

If you have any concerns about gestational diabetes during your pregnancy (or any other symptoms) our midwives are here to help. Book an online consultation for one-to-one online guidance today.

Kate, Naytal Midwife

Kate has been a Midwife within the NHS for more than 15 years and supports women to work harmoniously with their bodies and tune into their intuitions.

Diet and nutrition
Pregnancy symptoms
Second trimester
Third trimester

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