If my stomach is flat laying down, will it be flat after tummy tuck?

When I am examining a patient to determine how good I can make their tummy look with a tummy tuck, if their stomach is round when lying down then I know that they have some fat internally that will prevent me from making their tummy flat when standing. If it is concave when lying down, then chances are very good that it will be flat when standing. If your stomach is flat when lying down, then it MAY be possible to be flat when standing. However, I would caution you to expect there to be a little bit of roundness when standing anyway; it is normal to have a little bit of roundness even in the "perfectly fit" person with an ideal physique. 

Thank you for this great question! Yes, a bulging tummy present while standing which flattens out or becomes concave when lying flat is a very good predictive finding for a flatter tummy after tummy tuck. This is assuming a tight rectus muscle plication is performed during the procedure. Those individuals that continue to have a bulging tummy when lying flat suggests that excess fatty tissue remains within the abdominal cavity. These patients will obtain a better result if able to loose more of the intra-abdominal fat prior to the procedure.