LBT Question

[The Dude]

So here's the situation. My girlfriend (age 24) is thinking about getting a lower back tattoo, but she is concerned about its appearance later after she has kids (4 years or so down the road). It hadn't occured to me that the skin in that area would be effected that way by pregnancy, but I guess it seems reasonable.

Does anybody here know just how big of an impact pregnancy generally has on the appearance of LBTs?