How long does it generally take for a seroma to absorb?

I had incisional hernia repair surgery March 6th, (it was a large hernia, but he did it laproscopic doing 11 holes to do the repair) 2 weeks after surgery I thought the hernia was back, I went back to surgeon, they did a CT and it is a sernoma. He said he felt in my case it would reabsorb and didn't want to risk infection. He said it would take a long time for this to happen. Is he right? Its a little sore (has been from start), no fevers or anything unusual, its just... there