Breast augmentation and removal are common operations, easily obtainable by the general public for a variety of indications. Reasons for these operations range from cosmetic indications to cancer. Although breast appearance is definitely important as a secondary sex characteristic, breast size or presence are not involved in the legal definitions of sex and gender and are not important for reproduction. The performance of breast operations should be considered with the same reservations as beginning hormonal therapy. Both produce relatively irreversible changes to the body.

The approach to male-to-female patients is different than for female-to-male patients. For female-to-male patients, a mastectomy procedure is usually the first surgery performed for success in gender presentation as a man; and for some patients it is the only surgery undertaken. When the amount of breast tissue removed requires skin removal, a scar will result and the patient should be so informed. Female-to-male patients may have surgery at the same time they begin hormones. For male-to-female patients, augmentation mammoplasty may be performed if the physician prescribing hormones and the surgeon have documented that breast enlargement after undergoing hormone treatment for 18 months is not sufficient for comfort in the social gender role.
XII. Genital Surgery

Eligibility Criteria. These minimum eligibility criteria for various genital surgeries equally apply to biologic males and females seeking genital surgery. They are:

1. Legal age of majority in the patient's nation;
2. Usually 12 months of continuous hormonal therapy for those without a medical contraindication (see below "Can Surgery Be Provided Without Hormones and the Real-life Experience");
3. 12 months of successful continuous full time real-life experience. Periods of returning to the original gender may indicate ambivalence about proceeding and generally should not be used to fulfill this criterion;
4. If required by the mental health professional, regular responsible participation in psychotherapy throughout the real life experience at a frequency determined jointly by the patient and the mental health professional. Psychotherapy per se is not an absolute eligibility criterion for surgery;
5. Demonstrable knowledge of the cost, required lengths of hospitalizations, likely complications, and post-surgical rehabilitation requirements of various surgical approaches;
6. Awareness of different competent surgeons