I am 20 years old and after having my first baby 11 months ago (whom I breastfed for 8 months), I am so unhappy with my breasts!  They sag and are deflated and they seem much smaller.  From what I've read, it's best to do a breast augmentation when you are finished having children.  I do plan on having more children, but not for a few years.  I feel like I would be able to enjoy my implants long enough before another baby was expected.  Should I really wait on breast augmentation?

If you think it will be a few years  before possibly having more children, then your logic is reasonable and consideration of breast augmentation is certainly possible.  If you want silicone implants, you must wait until age 22 anyway, but saline augments could be done now.

I suggest you have an in-depth discussion with a board-certified plastic surgeon regarding all the pros and cons of this issue.

I would recommend going ahead with a breast lift and breast augmentation if you are truly unhappy with your breasts.  The sooner you have it done the more time you are left to enjoy your new breasts.  You do need to recognize that you may need a touch up when you've finished having children.

All decisions for surgery are a balancing of the risks and possible problems and complications against what the surgery will provide you.  From the way you worded the question, it seems as if you have already done this and answered your own question.  If you are willing to possibly have a revision after your next children are born in order to have the satisfaction that an augmentation would give you now, then, by all means, contact a Plastic Surgeon and go for it.