The results of a breast lift will vary from patient to patient. If the skin is of poor quality and if stretch marks are present, then one would expect the results of the breast lift to be shorter lived than somebody with healthy ideal skin.
The results of a breast lift will also depend on the technique employed. Many women want the breast lift to achieve fullness in the upper part of the breast. This fullness can be maintained longer if at least a small or medium size breast implant is placed at the same time.
It is best to wait until you are done with your childbearing years to have this type of surgery performed. Surgery should be delayed for at least three months after lactation has ended. Any pregnancy following this type of surgery can compromise the result and require additional surgery in the future.