Hi, I had a seroma after my operation and ended up in the ER late one night. Luckily one of the breast surgeons registrars was working that night and she said not to drain it due to the risk of infection. It was a bit funny, I was sitting there half naked and she was explaining to the nurse/doctor who was there all about seromas and why they don't drain them, and how they are made up , until I kinda coughed after about 5 - 10 mins and said "Can I put my clothes back on yet?" According to her, they are like sponges so draining them isn't the same as just popping a needle into a balloon and sucking out the fluid. It was an interesting lesson.