In mammals, an abortion is when a pregnancy ends early without the birth of babies. Abortions can occur naturally, usually because something went wrong with the pregnancy.

When this happens, it is called a miscarriage. Humans can also end the pregnancy on purpose before birth takes place. This is called an induced abortion. Its legality can depend on specific conditions such as incest, rape, severe fetal defects or the mother's health being at risk, although it depends on where the laws are.

See types of abortion
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