Is it permissible for a Jew to undergo elective surgery, such as cosmetic surgical procedures, nose adjustments, or the removal of embarrassing facial features?
Undergoing elective surgery potentially involves two prohibitions. Firstly, Halacha forbids causing oneself bodily harm unnecessarily. Therefore, although one certainly may undergo surgery that he requires for his medical well-being, allowing a surgeon to operate on one's body unnecessarily, purely for the sake of improving appearance, would seemingly be forbidden. Secondly, general anesthesia is looked upon as a situation of danger, and we might therefore forbid willingly subjecting oneself to general anesthesia unless this is necessary for his health.
Chacham Ovadia Yosef (in Yabia Omer) allows undergoing elective surgery where this is direly necessary. For example, if a single woman fears she will be unable to find a suitable match unless she undergoes the procedure, she may have the operation. This would apply as well to a married woman if she suffers humiliation or difficulties involving Shalom Bayit (domestic harmony) due to her features. In all these cases, the anguish the woman endures by her current condition exceeds the harm she would suffer as a result of the procedure, and therefore the prohibition of Chabala (causing oneself harm) does not apply. And as for the risks involved in general anesthesia, Chacham Ovadia writes that these procedures are generally brief and do not require deep anesthesia, and thus little or no risk is entailed.
In all other circumstances, however, Halacha would forbid undergoing elective surgery. If a woman wishes to have cosmetic surgery purely for the sake of improving her appearance, she should be discouraged from doing so for both Halachic reasons, as explained, and due to the broader, "Hashkafic" (ideological) problems involved in preoccupation with vanity and modern societal fads.
It should also be noted that Rabbi Eliezer Waldenberg, in his work "Tzitz Eliezer," disagrees with Chacham Ovadia's ruling, and forbids all elective surgery, even in the cases described above. He contends that if the Almighty formed a person in a certain way and gave him a certain appearance, he is not entitled to change it by undergoing a medical procedure.
Although we follow Chacham Ovadia's ruling, allowing elective surgery under certain circumstances, as discussed, a person considering elective surgery must very honestly assess his motivations for doing so, to ensure that he is driven by a genuine need, and not by a preoccupation in vanity.
Summary: One may not undergo elective surgery unless it is direly necessary, such as to find a spouse, save one's marriage, or avoid humiliation.