I'd say it would depend on your body size and the size of your babies.
My first was a large-ish baby and I had stretch marks all over my hips, stomach and around to my back. He seriously stretched me like nothing else. I have had 3 full term babies since him and not had one more stretchmark! lol
If I were to have had a tattoo where you're described it would be a horrid mess today. I have a friend who also has a badly over stretched tattoo in the same area.
I agree with Kirsty-Lee that it is best for you to ask the tattooist what they think.
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