Is It Okay to Wait 3 Weeks Before Stitches Are Removed after Mommy Makeover?

The good thing about suture removal is that your surgeon will be the best to know how long the sutures can stay in.  If you leave them in too long, that will for certain be a problematic scar situation where you can see railroad marks or cross hatching markings neither of which is desirable.  The ideal scenario is that they be removed exactly when he tells you (they don't necessarily need to be removed by a certain person, if your surgeon approves). 

Thank you for your question, The-most indicated person to give you a correct answer is your surgeon because he is the one who knows what type of suture used.
best regards,

Sutures are removed at varying times after surgery based on type of suture used and location on the body.  If your surgeon is not concerned about waiting 5 more days, I would rest assured it is okay to wait a bit longer. 

Most plastic surgery closure are done with sutures that run underneath the skin.    The majority of surgeons use sutures that are self absorbing and do not require removal.      Some use a running suture underneath that is pulled out from a point at the end the the incision.     These are okay to leave for weeks.     If sutures are placed where you see the knot or running baseball stitch, these will leave suture marks if they are not removed in 5-6 days.       Your surgeon most likely did not use that type of closure.

I would not wait another 5 days to have your stitches removed as they can leave permanent marks on your skin. 2 weeks is more than adequate for most wounds to have healed and so the stitches should be removed at that point.

Leaving permanent (removable) sutures in place for too long can indeed lead to a less ideal scar, with some degree of the "railroad tracks" that you mentioned.  That said, 5 additional days will likely not make a tremendous difference.  With my patients, I try to avoid this issue entirely by closing all tummy tuck and cosmetic breast incisions with dissolvable sutures that are beneath the surface of the skin.