I think I posted in the TOAT that I was having a lot of my Lansinoh bags leak when I'm thawing BM. I emailed the company and this is what they told me. I started laying them flat when thawing, but still having the same problem. Hope it's helpful for someone else!
"When thawing the rest, place in a glass or bowl by itself with no water, with the ziplock seal at the bottom, so milk thaws towards the seal. When thawed, snip the bottom end with a scissors and pour milk into bottle."
Re: Lansinoh BM bags