Women who undergo breast reconstruction with implants immediately after having a mastectomy are much more likely to experience complications if they smoke or are obese, a new study has shown.

Women who want to undergo breast reconstruction after a mastectomy have two main options - implants or autologous reconstruction, in which a woman's own tissue is used. The implants option is less invasive.

"The goal of our study was really to determine which patients are at greatest risk for experiencing significant complications with their implants in the first 30 days after breast reconstruction, with the hope that it will allow practicing surgeons an opportunity to better tailor pre-operative risk counseling and improve patient selection," explained the study's lead author, Dr John Fischer, of the Hospital of the University of Pennsylvania.

The researchers analysed data relating to over 14,500 women between the ages of 40 and 60, who had undergone immediate breast reconstruction following a mastectomy.

It is already known that smoking and obesity can affect a patient's healing time, however this study found that women who smoked were three times as likely to suffer implant loss (the unplanned removal of an implant for any reason) in the first 30 days. They were also up to three times more likely to suffer implant loss if they were obese.

"One of the novel findings in our study is that it is not just obesity, but it is a state of progressive obesity that is associated with poorer outcomes. The more severe the state of obesity, the higher their risk of this complication," Dr Fischer explained.

Other factors that increased the risk of implant loss in the first 30 days included being over the age of 55 and undergoing bilateral reconstruction - having two implants done during the same procedure.

The researchers found that the more risk factors a woman had, the greater her risk. For example, an overweight smoker who is older than 55 will be at significantly more risk than a younger normal-weight non-smoker.

"If a patient learns she has a high risk for complications with breast implants, she may choose to have an autologous tissue-based procedure. The risk might not be worth it, or on the other hand, the patient accepts the risk. Either way, the expectations are better managed and overall satisfaction is likely to be higher," Dr Fischer added.

Details of these findings are published in the Journal of the American College of Surgeons.