First of all I would like to say that I do not have implants nor have I ever considered them because I have more than I ever wanted. LOL But I am an x-ray tech who has been certified in mammography for the past 20 years. I have preformed mammograms on hundreds of women with implants and while that makes me far from an expert I would just like to share a few things with you.
Picking a surgeon is absolutely critical! I have seen some horrible looking implants and very few that are natural looking. Pick a surgeon in a larger metropolitan area that does augmentation surgeries several times per week. Practice makes perfect applies to surgeons too.
Make sure you throughly understand and can live with any complications or less than perfect results. One big problem I come across regularly is breasts implants that are hard due to a build up of scar tissue around the implant, encapsulating it. Also leaks and ruptures do occur. Most patients I have talked to that have had their implants for a long period of time have had to have them replaced at least once. I would ask the surgeon about how long they generally last. Implants also limit the sensitivity of a mamogram which could lower the chance of a breast cancer being found early. Make sure you throughly understand all the risks.
Most women are unable to keep weight off long term so think about weather you would be happy with a D cup or larger if you put the weight back on.
Lastly make sure you are doing this for you! I have seen many women who had implants for a boyfriend or husband and have later regreted it.
Hope this has helped some, good luck