Oophorectomy is the surgical removal of the ovaries of a female animal. In the case of non-human animals, this is also called spaying. It is a form of sterilization.

The removal of the ovaries together with the Fallopian tubes is called salpingo-oophorectomy. Oophorectomy and salpingo-oophorectomy are not common forms of birth control in humans; more usual is tubal ligation, in which the Fallopian tubes are blocked but the ovaries remain intact.

In humans, oophorectomy is most usually performed together with a hysterectomy - the removal of the uterus. Its use in a hysterectomy when there are no other health problems is somewhat controversial.

In animals, spaying involves an invasive removal of the ovaries, but rarely has major complications; the superstition that it causes weight gain is not based on fact. Spaying is especially important for certain animals that require the ovum to be released at a certain interval (called estrus or "heat"), such as cats and dogs. If the cell is not released during these animal's heat, it can cause severe medical problems that can be averted by spaying or partnering the animal with a male.

Oophorectomy is sometimes referred to as castration, but that term is most often used to mean the removal of a male animal's testicles.

See also

Upper house

An upper house is one of two chambers of a bicameral legislature, the other chamber being the lower house. Upper houses are known by a variety of titles, but the most common is senate. An upper house is usually distinct from the lower house in at least one of a number of ways. An upper house may:



One exception to the principle of the upper house having less authority than the lower house may be the United States Senate. This is often referred to as the 'upper house' of the legislature but is in vital respects more powerful than the House of Representatives (the 'lower house').

Election or appointment


Many jurisdictions, such as Denmark, Sweden, Venezuela, New Zealand, and the Canadian provinces of Quebec, Nova Scotia, Prince Edward Island, Manitoba and New Brunswick, once possessed upper houses but abolished them, to adopt unicameral systems. Newfoundland had a Legislative Council prior to joining Canada, as did Ontario when it was Upper Canada. The Australian state of Queensland also used to have a legislative council, which it abolished in 1922, but all other Australian states continue to have bicameral systems.

Titles of upper houses

See also

Last updated: 02-06-2005 21:01:06