I used these bottles for my first baby for over a year and I never had problems with leaking from the bottom. If I did, It was my fault (didn't tighten enough, gasket was lopsided etc). The nibbles towards the end started leaking, only b/c they were in need of replacement. I will be using them for our next baby after I find replacment nipples!

I used these bottles for my first baby for over a year and I never had problems with leaking from the bottom. If I did, It was my fault (didn't tighten enough, gasket was lopsided etc). The nibbles towards the end started leaking, only b/c they were in need of replacement. I will be using them for our next baby after I find replacment nipples!