Abortion has a long history and has been induced by various
methods including herbal abortifacients, the use of sharpened
tools, physical trauma and other traditional methods. Modern
medicine utilizes medications and surgical procedures to induce
abortion. The legality, prevalence, and cultural views on
abortion vary substantially around the world. In many parts of
the world there is intense public debate over the ethical and
legal aspects of abortion. The approximate number of induced
abortions performed worldwide in 2003 was 42 million, which
declined from nearly 46 million in 1995. Spontaneous abortion
(also known as miscarriage) is the expulsion of an embryo or
fetus due to accidental trauma or natural causes. Most
miscarriages are due to incorrect replication of chromosomes;
they can also be caused by environmental factors. Spontaneous
abortions, generally referred to as miscarriages, occur when an
embryo or fetus is lost due to natural causes before the 20th
week of gestation. A pregnancy that ends betw