Is it permissible to perform a cosmetic surgery to lift the breasts due to their sagging from pregnancy and childbirth, knowing that it does not involve reduction or enlargement, but rather a tailoring of the skin?

Cosmetic surgeries are permissible for removing disfiguring defects, but not for increasing beauty. Sagging breasts resulting from pregnancy and breastfeeding is a natural occurrence and not a disfiguring defect. Therefore, performing cosmetic surgery on them falls under the category of seeking to enhance beauty and altering Allah's creation, which is prohibited. However, if the sagging causes harm, disfigurement, or illness, then it is permissible to remove this harm.