I will be 3 weeks post op tomorrow from a tummy tuck and have a decent size hematoma. Will this reabsorb? (photo)

Regardless of its composition (serum or blood), the collection may well lead to this area not adhering to the underlying layer without re-operation. This needs to be aspirated, drained, or surgically removed, all of which are minimal compared to what time, money, and surgery you have invested thus far.See your surgeon immediately; the longer you wait, the higher the likelihood of developing a pseudobursa, which has an even higher risk of requiring re-operation to resolve. This is not an emergency as you ahve had this collection for at least a portion of the past 3 weeks, but it IS an urgency. Call your surgeon's office first thing tomorrow and be seen ASAP. Best wishes! Dr. Tholen.

It's difficult to tell what happening from your photo. Typically, a true hematoma that requires surgery to clean out presents in the first 24-48 hours after the procedure. You would be very uncomfortable and your abdominal tissues would be super tight. A small blood collection is common and not typically a problem. Considering all of the above, I would reccomend working closely with your surgeon for appropriate postoperative care.Good Luck

This is something to be concerned about for sure. This appears to be quite a sizeable hematoma that could result in issues down the road. If the skin is tight and the abdomen is tender, I would suggest having the hematoma evacuated. If the skin is soft and the hematoma is starting to liquify, I would probably try to aspirate the heme fluid or place a seroma-cath. It is possible that the body could just resorb this, but I would discuss the other options with your surgeon. 

If your drains are not working then it cannot decompress.  It needs to be removed and the area drained properly.

Great question for your surgeon.......if you are going to the web for info  because that's what your surgeon said.     ........... get a second opinion.