If you are desiring a firmer look and feel to your breasts an implant is the most likely to achieve this, though there will be some increase in size with the addition of an implant. If you would like to avoid implants the only permanent alternative at this juncture is fat transfer. This will modestly increase the size of the breast, but is unlikely to make the breast "firmer" as you suggest. I would recommend that you seek a consultation with a plastic surgeon to further discuss your aesthetic goals and options to achieve them. Best wishes, Dr. Meghan Nadeau, Seattle, WA
Thanks for your question. The options we have at present are limited to fat injection or silicone implants. There are pros and cons to each of these techniques. Please do not waste money on creams or devices that use radiofrequency, ultrasound os similar as all will have only a very small and temporary effect , just like the cold weather!
See a BAAPS or BAPRAS approved surgeon to discuss your options
Your options are limited to either implants or autologous fat grafting. Both can make your breast size larger, but fat grafting is a bit more limited in size you can achieve. Fat will also be softer. Becoming firmer and more than just a cup size larger will likely require implants.
Options for breast enlargement other than implants
There are basically two other described ways to enlarge breasts without using a prosthetic implant. Fat grafting of the breast will enlarge it but not necessarily make it feel more stiff like you are describing. There is a technique called Brava which is essentially a suction bra to expand the breast with negative pressure. There is also a combination of first doing the Brava and then placing fat grafts. All of these methods necessitate that you have a fair amount of fat that you can remove from around the abdomen, hips, and legs. I recommend that you find a plastic surgeon in your region that is familiar with these modalities. Good luck.