Breast augmentation in general, is a very safe procedure. Life threatening complications are very rare. Some other complications are
Capsular contracture:
The body forms a thick skin like structure around the implant. This layer may shrink over a period of time. This can cause some pain or a feeling of heaviness, hardness in the breasts. It is possible to treat such cases by surgery. Sometimes the implant has to be changed. Capsular contracture is less likely to happen with saline filled implant.
Implant rejection:
Implant is essentially an external material. The body of some patient may not accept this material. If this happens, the implant is removed and the breast get back their original size and shape.
Implant rupture inside the body:
This can happen with some injury to the body. If this happens with the silicone gel implant, the gel leaks out in the surrounding tissue and has to be removed. If this happens with the saline filled implant, the saline that leaks out mixes with the blood. This saline is the same that is given in veins by the doctors. It is therefore harmless. In any case the breasts return to their preoperative size. The remaining implant has to be removed. It may be possible to place another implant while removing the ruptured one.
Change of sensation around nipple:
In some cases there is a sensation of tingling and numbness or absence of sensation soon after operation. This returns to normal in about 6 weeks to 6 months.
Bleeding and Infection:
It is to be noted that all these complications are uncommon and not all the complications would occur in a given patient.
Can this operation cause Cancer?:
So far it has not been noticed that putting an implant behind the breast can cause cancer. It is however essential to inform your doctor about the implant when he/she examines the breasts. If the breasts have to undergo x-ray (Mammography), then the doctor should be informed so that he can change the x-ray factors.