Why can't I tan my stomach after a Tummy tuck?

Its not typically advice I give my patients but, he/she may have reasons I'm unaware of. Good luck

If you are having a regular tummy tuck, you will undoubtedly have a scar around your belly button as well. UV radiation causes hyperpigmentation (brown discoloration) of healing scars for more than a year after surgery. Your surgeon is probably thinking of providing you with the very best result possible and wants your scars to look great!

I am not sure why your PS told you this, but here are some instructions I give.  Usually after a tummy tuck the lower midline area is often numb and you can burn yourself seriously.  It will take several weeks to months for the numbness to clear.  Also because it is numb any heat can burn you here as well.  Be careful about both.  Also immature scars will tan darker and will make the scars more visual.  Scars take up to a year to mature.  Best of luck with your procedure.  Generally, I think this is good advice. 

Every plastic surgeon has different suggestions for postoperative care and you trusted you surgeon enough to let him operate on you should you should listen to his advice.    In  darker skin types there could possibly be hyper or irregular pigmentation in areas that were recently operated on but I haven't seen this in abdominoplasty.  One thing to be careful about is the numbness.  I did have one patient who fell asleep in the sun and got a bad sunburn of her lower abdomen due to that part being numb.  Be careful.

If you're having a full tummy tuck, then you will probably have a scar around your belly button as well as the one going across your lower abdomen.  Both scars, while still fresh, can discolor with tanning.  You'd have to cover the belly button while tanning your stomach, which would give a strange-looking tan.  In addition, the recently manipulated and stretched skin may tan unevenly.  And you've probably already been warned that tanning in general can cause skin cancer, age spots, and wrinkles.