Difference in Glucose Tolerance Test depending on hospital?

[Redfairy1288]

Hi all

I recently had a GTT as i have PCOS so that's a trigger for the test. The hospital I'm with took my blood 3 times. Once when I arrived after fasting, then gave me the glucose drink and then took blood after 1 hour and then again after 2 hours.

I was called with the results 3 days later which showed that the first and third readings were absolutely fine, but the second one (after 1 hour) was slightly high. It was 10.1 and should have been under 10. Based on this, I have been diagnosed with Gestational diabetes.

I went through 2 weeks of overwhelm, guilt and stress over what this all means. I attended a session where they went over all the risks and it really upset me and felt too much to take in. I've seen a dietician.

I now have to finger prick to check my levels 3 times a day before/after each meal and record a log. I also have to have 4 more ultrasound scans to monitor the baby's growth and see consultant. It means I'm now classified as high risk and can only go 6 days overdue before i would be induced.

I have found out in the last few days that someone i know who is under a different hospital had a GTT and her blood was only taken twice; once after fasting and then 2 hours after the glucose drink. Her results were fine and she was not diagnosed with GD. If i was under her hospital, my results wpuld have been fine too as my first and last readings were good. My midwife has also said that another hospital in the county does it this way and if i was with them i wouldn’t have been diagnosed with it.

I am very confused as to why different hospitals are doing this test differently and its meaning some people are being diagnosed with GD when in another hospital they wouldn't be and some are being told they don't have GD when another hospital would say they did.

Does anyone have experience and/or knowledge of why this is?

It will of course be lovely to see my baby on screen again 4 more times, and the extra monitoring will certainly ensure all is ok which is good. But its a lot to put me through if some trusts would say i didn't actually have it.

So confused

Xx

Was your friend given the exact same amount of glucose to drink?

I believe so yes xx

I’m a midwife but don’t work in clinic so have t done a GTT for ages. However it’s bloods on arrival and then 2 hours after the glucose. Cut off for diagnosis was 7.....but I did hear someone saying that this has been changed recently and now even more women are being diagnosed as diabetic.....so not sure if there’s some new national guidelines we’ve adopted.

Oh and we wouldn’t have tested you in the first place as PCOS isn’t a trigger.

www.nice.org.uk/news/article/new-thresholds-for-diagnosis-of-diabetes-in-pregnancy

Cut off has increased but to 7.8

Sorry that’s 7.8 at 1 hour....so nice do talk about different figures for fasting, 1 hr, and 2 hours which ties in with your 3 tests. Figures here are mmol/litre. Was your 10.1 measured in mmol/litre?

Sorry I’ve read that all wrong, the 3 figures are target levels, so if you’ve been diagnosed whatbyou should stick to.

For the actual test it just talks about a fasting level which should be below 5.6 and a 2 hour level which should now be below 7.8.

Yeah that's the funny thing, on all the legit medical websites I've looked at (diabetes uk / nhs etc) it just talks about a fasting test and then a test at 2 hrs. No mention of one after 1 hr. The websites also don't list PCOS as a trigger for the GTT but in my case as soon as i told my community midwife at booking that i have PCOS she was "right you'll have to have a GTT". I didn't mind having the test really but i was knocked for six with the diagnosis - as described in my original post - the overwhelm caused me to have 2 weeks signed off with anxiety about it & even now i am finding the finger pricking to test my blood 3 times a day quite painful and a big thing each day. If im at home all day then i tend to remember to do it (i have to test before i eat on some days, which must also be at least 2 hrs since i last ate, and some days i have to test 1 hr after ive eaten) but if i go out for some or all of the day or am travelling then i do often forget..

Then to start hearing from friends who are also pregnant in other areas that they only had bloods taken twice so were not diagnosed but mine were taken 3 times and the 1 hr one was just over what it should be - meaning if I'd been with another hospital i wouldn't have been diagnosed. After my post here I did contact the midwives at my hospital about this who said the following:

" This is common across all NHS trusts to have different policies for all areas of the care …

the NHS does not stipulate a national guideline for all trusts to follow

the reason we have a tighter guideline is because the Diabetic team here looked at the current research and could see that a tighter criteria meant there were less women missed who have gestational diabetes ...so less harm comes to mothers and babies"

My fasting level and 2 hr levels were within those remits / targets you describe. I was just told that my hospital also have a 1 hr target of 10 mmol and as mine was 10.1 I'm diagnosed with it. No borderline - in their view I simply have it and that's that :(

Yeah I can see why you're not happy. You wouldn't be diabetic where I work and we have a shit hot diabetic specialist midwife who knows her stuff and has recently updated guidelines which are in line with NICE.

I do get the midwives point that sometimes new research comes out after a nice guideline which makes a hospital feel they need to change their guidelines.

Their local guideline will be referenced. I don't think it would be inappropriate to ask to meet someone to explain what research they're basing it on.

Thankyou for your helpful responses. I have a follow up appointment on monday with the GD team anyway; i shall write down my questions and ask them to explain this more. I am wondering if i should ask to be re-tested? But then if the results are the same the outcome would be the same. Also obviously its not very nice spending over 2 hrs sitting in hospital having blood taken 3 times, but wondering if i should...