Gestational diabetes test

[swiftt]

I had a fasting blood test (HbA1c) at my booking bloods and 28 week bloods to test for GD. My BMI is over 30, no other risk factors. MW told me that my trust have restarted the oral GTT but didn’t want to reschedule my appointment, even though she said the blood test isn’t as accurate. My results have come back normal, but NICE guidelines recommend not using this blood test and using the oral GTT. Should I be asking for the GTT, or just assume the blood results are enough? Also think it may be too late for the OGTT anyway? I’m 30 weeks this week.

I guess it's up to you personally.

If your fasting bloods were completely normal range and not even slightly raised, I'd probably not bother. But it's personal preference

@SnooperTrooper12345 they were normal. It’s just the NICE guidelines stating that the blood test shouldn’t be used for GD screening that is making me a little anxious. I’m always a bit on edge about things being missed. I’ll have a think about it!

I had GD with my previous pregnancy, the fasting blood test wouldn't work for me as my fasting last time and this time is within normal range it's the after sugar where last time I shot you. I think it needed to be below 7.8 and it was 11. I have 17 wks this pregnancy and got tested early due to previous gd, so far i haven't developed it but will be tested again at 26 wks using full GGT again.

I think you would most likely have other tell-tale signs...high levels glucose in urine samples is quite a common one, and at your stage of pregnancy, the growth of the baby. (GD can result in babies having an unusually large abdominal measurement. It can also cause babies to be smaller than expected). So it would likely be picked up due to a combination of things. Given that your fasting blood was normal, and I'm assuming you've had nothing else unusual crop up, I think you're probably fine. However if you really want peace of mind you could push for a GTT. There is a lot of info on a fab website called Gestational Diabetes UK if you want to read around a bit. X

[quote swiftt]@SnooperTrooper12345 they were normal. It’s just the NICE guidelines stating that the blood test shouldn’t be used for GD screening that is making me a little anxious. I’m always a bit on edge about things being missed. I’ll have a think about it![/quote]
As a PP said, you'd have signs, like in your urine sample so it wouldn't go completely missed if you did have it

If your only risk factor is a higher BMI I wouldn't request another test. Like others have said if you do develop GD there will be other signs of it along the way.

I get tested for the same reason, 3 pregnancies I've had the full testing (x4) and all came back normal.

Ah, good to know! I’ve no symptoms, my urine was clear and I ended up having a growth scan at 28 weeks due to consistently reduced movements and was told that she is extremely average so that’s another good sign. Fundal height was measuring a week ahead at my last appointment, but I know how inaccurate that can be. I’ll not subject myself to the full OGTT if it’s not necessary.

I don't want to be that one who just contradicts everyone but in case others also use this thread. I never had other symptoms, no glucose in my urine, my son wasn't measuring large etc. Just so people know it does happen.

I agree with @Crazylemon86 I'm afraid.

HB1AC isn't a fasting blood test, it's an average sugar level over the last 12 weeks and shouldn't be used for diagnosis of GD. Did you have that as well as a fasting blood test?

My fasting bloods were fine, as was my hb1ac and I never had glucose in my urine but I failed a GTT with my DS.

With this pregnancy, I passed everything up until 28 weeks and then by 29 weeks I noticed my numbers starting to creep up as I self monitor at home.

Also, just to note GD doesn't always cause big babies. It's a misconception although it definitely can.

Odds are you don't have it but if you're worried then I would ask for the test. I had no risk factors but these things happen.

@Crazylemon86 @Teakind oh, now I’m conflicted! I was told to fast before the blood test so assumed it was a fasting blood test but my notes only show the result of the HbA1c test.

@swiftt what was the result of your hb1ac? If it’s really low maybe that’s how they’ve decided you don’t need a GTT but it seems odd.

I think lots of ladies have been given an hb1ac during the pandemic instead of proper glucose tolerance testing which personally I think is disgraceful. They are going to miss a lot of ladies with GD that way.

As I said previously though, odds are you don’t have it but if you are worried then ask for the GTT or at least a fasting blood test. Sometimes it feels like there’s one thing after another to worry about in pregnancy doesn’t it!

@Teakind 32mmol? I just spoke to my mum who happens to be a specialist diabetes nurse, she thinks I’m worrying over nothing and that the blood tests are accurate - even though I told her about the NICE guidelines and why would they usually do the OGTT if the blood test will suffice? I just feel a bit palmed off by my midwife in general. I may ask for the full test just to put my mind at ease, especially since I won’t be seeing midwife for another 3 weeks.

I was given just the fasting blood test. I don't know if it was a normal fasting blood test or the same as what you had.
Either way I didn't have the proper GT test..

I said to my partner at the time that if they can tell from that then why do they do the 2 hour one.
But clearly that isn't the case!

@swiftt that’s a lovely result!

The problem with using it for diagnosis of gestational diabetes is insulin resistance tends to manifest itself at around 26/28 week. As the hb1ac is an average of 12 weeks, a result would be lowered by the previous weeks before insulin resistance kicked in.

Odds are definitely in your favour but I do understand the feeling to get things double checked. With this pregnancy, I’ve been monitored throughout (as had it in a previous pregnancy) and after getting to 28 weeks with no signs, I was signed off and told I didn’t need to test anymore. Lucky I did anyway as it kicked in a week later.

@Teakind thank you so much for explaining that, that makes sense now!