Foul odor and leakage from belly button after hernia repair with tummy tuck?

I'm sorry to hear about this odor. The drainage and the odor is suggestive of a wound that's having difficulty healing. Infection must be ruled out, so go see your plastic surgeon!Best wishes, Dr. ALDO 

A would odor could represent an infection. It may be related to an area that has not healed or might be related to an exposed suture.  Best to be seen in person.

Occasionally belly button leak a bit after surgery.  They tend to get very swollen and can leak serous (yellow colored) liquid.  However, a foul odor is NEVER a good thing.  It typically means an infection.  This is especially true if the liquid is opaque or thick.  See your doctor ASAP to get some antibiotics.