Belly size shouldn't ever change your due date. It's changed for LMP and ultrasounds. You can ovulate early or late which can throw off your due date. If you don't have normal cycles, growth and development of the baby can give the provider a better idea of gestational age. Mine changed at ultrasounds and we figured out that I had a period while I was already pregnant ( which is common) so I was a month ahead of what we thought.

Still curious why theeu changed the due date

I'm due Oct 5th but pretty sure they might take her early since I have GD. :(

Due October 5th & FTM ??

I'm due Oct. 5th too and I'm a FTM!!! ??

When were you due??

What made them change it , your belly size or ultrasound

I'm due October 9th and also a FTM

Mine has changed 3 times lol. Went from OCT 26, to the 15 now OCT 1. This is my second and I never had my due date change with my first. Oh well, baby will come when he/she wants to. :) congrats on your little one!