I doubt it would ruin them but then again that would be the least of your worries if that were to happen. Lol
No it won't ruin your carpets but you definitely want to put something thick like a big towel Down in your car when ur on your way to the hospital because the water randomly keeps flowing out lol
I've had to have my water broken for me with 5 of my babies.(I'm on # 6) and only one of them, when I sat up gushed all over my nurse's shoes. Althoughit was gross I don't think it would stain. It only had a little blood.
I have had my water break everywhere! Lol on my 6 th pregnancy. It has broken on a sofa, in a car, even in the dining room of a restaurant!Never stained!
oh good one less thing on my worry list :)