If that doesn't solve the problems I would add neutering at the right age.
So no, you shouldn't breed your dog — even once.
No one is sure why obesity is seen more in spayed females, as no studies have shown a change in metabolism after the procedure.
Regardless, veterinarians perform so many of these procedures that we consider them fairly routine, even in large dogs, and the overall complication rate is still very low.
She may mount other dogs herself or hump pillows or stuffed toys.