Understanding Gestational Diabetes: Testing, Accuracy, and Impact on Birth and Choices

Beyond the Bump
Jul 6, 2023
3 min read

Updated: May 18

Let’s talk about gestational diabetes (GD) — not with fear, but with facts. This is one of those topics that gets discussed a lot in pregnancy, and often in a way that ramps up anxiety and confusion. But when we dig into the evidence (hello, NICE guidelines 👋), things are often a lot more balanced than we're led to believe.

💡 What Is Gestational Diabetes?

Gestational diabetes is a condition that affects how your body processes sugar during pregnancy. It usually pops up in the second or third trimester, and while it sounds serious (and should be taken seriously), it's also:

Common (affecting up to 16% of pregnancies in the UK depending on criteria)
Manageable with the right support
And not always the reason for an early birth or induction that it’s often made out to be

How Is GD Tested?

In the UK, you're usually offered the oral glucose tolerance test (OGTT) around 24–28 weeks — or earlier if you have certain risk factors.

Here's what the OGTT involves:

You fast overnight (yep — even though we're told not to fast in pregnancy 🙃)
You go to the hospital and have a blood sample taken
You drink a very sugary drink (like flat Lucozade)
You wait 2 hours
Another blood sample is taken

It’s not exactly a comfy experience. And it’s not your only option.

There Are Alternatives to the OGTT

If fasting isn’t suitable for you, or you want a more real-life picture of your body’s glucose response, you can ask about:

Home blood glucose monitoring (testing blood sugar before/after meals over several days)
HbA1c testing (a long-term average of blood sugar levels)
Random blood glucose tests in some circumstances

You are absolutely allowed to question whether the OGTT is the right test for you and ask for alternatives. And we walk you through how to have that convo with confidence in The Birth & Baby Academy.

How Accurate Is It?

The OGTT has value — but it’s just one snapshot on one day. People who “fail” it by a tiny margin are often classed as high risk, even if:

They’ve had no symptoms
They feel well
Their ongoing blood sugars are stable

Every NHS trust sets their own threshold for a GD diagnosis, so you could be “positive” in one area and “normal” in another. 🤯

What If You’re Diagnosed?

If you're told you have GD, the NHS pathway may include:

Referral to a diabetic midwife
Seeing a dietitian
Regular growth scans
Blood sugar monitoring at home

If your GD is well controlled through diet and/or lifestyle, the latest evidence — including from NICE — says you are not automatically higher risk than anyone else.

Big baby? That gets thrown around a lot — but it’s worth knowing:

NICE specifically states that a suspected large baby alone is not a reason to induce.Induction based on size alone is not evidence-based.

Let that sink in. You’re allowed to say, “I'd like to see the evidence for that recommendation.”

🗣️ So What About Birth Choices?

Just because you’ve been diagnosed with gestational diabetes doesn’t mean:

You must be induced
You must have a c-section
You must birth in a hospital

You still have all your rights. You still get to ask questions. You still get to say yes or no. We love empowering people to make those choices — and if you're not sure how to even begin those conversations, watch our free video "Take Control of Your Birth" where we walk you through it, step by step.

We are very pro-choice over here, so if you decide a Caesarean Birth is the right option for you, then download our FREE Caesarean Birth Plan Template & plan the empowered Caesarean birth that you deserve.