A hysterectomy (from Greek hystera "womb" and ektomia "a cutting out of") is the surgical removal of the uterus, usually performed by a gynecologist. Hysterectomy may be total (removing the body, fundus, and cervix of the uterus; often called "complete") or partial (removal of the uterine body but leaving the cervical stump, also called "supracervical"). It is the most commonly performed gynecological surgical procedure. In 2003, over 600,000 hysterectomies were performed in the United States alone, of which over 90% were performed for benign conditions. Such rates being highest in the industrialized world has led to the major controversy that hysterectomies are being largely performed for unwarranted and unnecessary reasons.

Removal of the uterus renders the patient unable to bear children (as does removal of ovaries and fallopian tubes), and changes her hormonal levels considerably, so the surgery is normally recommended for only a few specific circumstances:

• Certain types of reproductive system cancers (uterine, cervical, ovarian) or tumors
• As a prophylactic treatment for those with either a strong family history of reproductive system cancers (especially breast cancer in conjunction with BRCA1 or BRCA2 mutation) or as part of their recovery from such cancers
• Severe and intractable endometriosis (overgrowth of the uterine lining) and/or adenomyosis (a more severe form of endometriosis, where the uterine lining has grown into and sometimes through the uterine wall) after pharmaceutical and other non-surgical options have been exhausted
• Postpartum to remove either a severe case of placenta praevia (a placenta that has either formed over or inside the birth canal) or placenta accreta (a placenta that has grown into and through the wall of the uterus to attach itself to other organs), as well as a last resort in case of excessive postpartum bleeding
• For transmen, as part of their gender transition
• For severe developmental disabilities

Although hysterectomy is frequently performed for fibroids (benign tumor-like growths inside the uterus itself made up of muscle and connective tissue), conservative options in treatment are available by doctors who are trained and skilled at alternatives. It is well documented in medical literature that myomectomy, surgical removal of fibroids with reconstruction of the uterus, has been performed for over a century.

The uterus is a hormone-responsive reproductive sex organ, and the ovaries produce the majority of estrogen and progesterone that is available in genetic females of reproductive age.

Some women's health education groups such as the Hysterectomy Educational Resources and Services (HERS) Foundation seek to inform the public about the many consequences and alternatives to hysterectomy, and the important functions that the female organs have all throughout a woman's life.