I'm 5'8", Weigh 115 Pounds, Am a 32C. but They Are Saggy.

Depending on the rate of sagging, you may find that an implant with a smaller base width to make your breasts project more forward from your chest wall and body can be sufficient, making a breast lift unnecessary. Consider the Allergan Inspira TruForm 2 implant.

The exact procedure is hard to tell without an examination.  Most likely if you were happy with the shape of your breasts before you lost weight ( I am assuming that is why they have decreased in size) and you have not been pregnant and breast fed, then most likely you need just an augmentation.  Many people however have naturally droopy breasts and would need an augmentation and a breast lift to get a nicer bigger shape.

Droopy (ptotic) breasts cannot be improved with exercise.  If you are happy with your current size, your breasts can be lifted by having the excess skin removed (a breast lift - mastopexy).  There are several different types of lifts, each creating a different scar pattern, but all breast lifts result in scars on the front of your breasts.  If you desire more volume, breast implants can increase your size and fill out some of the extra skin.  Either of these options, or a combination of both may be appropriate for you, depending upon your desires and your current breast appearance.  A consultation with a board-certified plastic surgeon should help you decide which procedures would help you to achieve your goal.

Good luck.

My response to your question/post does not represent formal medical advice or constitute a doctor patient relationship. You need to consult with i.e. personally see a board-certified plastic surgeon in order to receive a formal evaluation and develop a doctor patient relationship.