Oh gosh, I totally understand the mix of hope and worry you're feeling right now, I had GDM with my second and the anxiety around baby's size and delivery options was very real! My own baby was measuring on the larger side too, and my gynae kept a close eye on me from around 36 weeks, so I know how much those growth scan numbers can stress you out. From what I've heard among mums going through similar situations, a big baby with GDM does make VBAC trickier but not impossible, the key seems to be having a gynae who is genuinely experienced with both GDM and VBAC cases, and who will monitor you very closely heading into the later weeks. My friend delivered at NUH and said their team was quite thorough with GDM management, with specialists from different areas working together rather than just the gynae alone, which gave her a lot of confidence. One thing mums have mentioned is that GDM babies are often recommended to be delivered from 38 weeks rather than waiting close to 40 weeks, so do clarify with your doctor what the plan is if things progress or if baby keeps measuring large, as that timeline really affects your VBAC window. Some mums have gone on to have successful VBACs even with a bigger baby, while others found that the size meant their doctors eventually advised otherwise closer to delivery, so it really does depend on how things develop week by week. The most important thing is staying in close communication with your gynae and asking all your questions openly, because your situation is unique to you. Wishing you all the best, you've got this!