The Sponge and Discharge

My girlfriend and I had sex on Thursday night. We used a Todays Sponge. Afterwards she went to the bathroom and said it had fallen out. Knowing she was supposed to leave it in for six hours, she put a new one in. We had sex the next day at 3 p.m. and she left it in till almost 10 p.m. After she took it out she said a lot of white stuff came out of her. Didn't think it was a big deal. The next day she said some more came out. Everything was fine after that, Until Sunday. She called from work and said she had been "leaking" the white stuff all day. And then today she said she woke up "yucky" and went to work, and the same thing happened. She said not quite as bad, but still all day. We have been searching the web for someone with a similar experience to no avail. Has anyone heard of or experienced this? Should we be worried? She said its not quite like a yeast infection. We don't know what's going on. Thank you in advance for any help.