I think it also depends on how strong your tummy muscles are too... I am only a size 6-8/ used to exercise exessively along side my DP who is a body builder (natural - no steriods). I really haven't noticed anything, but at my scan they said my uterus had swollen to the size of a orange. Again the abdomen muscles, perhaps that's why second time mum's pop sooner!
I am almost 16 weeks and in the last week have started to show slightly. I can just squeeze into normal pants, but can't do up the top button. I find trackies and elastic skirts are the most comfortable right now, or low hipster jeans. Can't wear those to work though!
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