I was scheduled to do mine at 28 weeks, the only reason I remember was that my urine tests at my 16-week check came back with really high sugar levels and my doctor was reluctant to send me for the glucose challenge because 'we don't usually test until 28 weeks'... I was like, 'YES BUT I HAVE HIGH LEVELS SO WOULDN'T IT MAKE SENSE TO TEST NOW AS WELL SO I CAN FIND OUT IF I HAVE BLOODY GEST. DIABETES?!' (Because my diet leaves a lot to be desired so I wanted to know if I had it or not in order to make some changes, kwim?)
She eventually sent me off and it came back clear... and I ended up not going for my 28-week glucose test because I haven't been going to hospital antenatal checks, just my GP (and she assumes I'm going to the hospital as well so doesn't send me for any tests, just checks the heartbeat lol).
So yeah, sorry for the ramble hahaha, I'm pretty sure it's 28 weeks.
28wks unless you've had gd before, high family history, multiple birth (but then not always) or seem to be balloning all of a sudden, then it's anywhere between 25-28wks.
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