Will Fractional CO2 laser on breasts give me the results I desire?

Absent a physical exam it is difficult to understand both the extent of your concerns or what treatments may work to correct the concerns. I have had great success with such treatments and a few disappointments. It really depends on a number of factors.  
Many factors come into play such as, age, social habits, general health, medications and so on. These factors will affect both the initial outcome and longevity of the treatment. 
If less than a 30% contraction of tissue is required, it may well be possible to achieve good results with a combination therapy. These treatments can, but generally do not include Co2 lasers.
Warmly,
Arbella Sarkis, MD   

Fractional and full ablative CO2 can help tighten the skin on the face, but they do not do an exceptional job on the body.  Body skin is different than the skin on your face.  It is usually very thin and does not respond to lasers as well as facial skin does.  Breast augmentation or a breast  reduction is the recommended treatment for loose skin on the breasts.