Abortion law permits, prohibits, restricts, or otherwise regulates the availability of abortion. Abortion has been a controversial subject in many societies through history on religious, moral, ethical, practical, and political grounds. It has been banned frequently and otherwise limited by law. However, abortions continue to be common in many areas, even where they are illegal. According to the World Health Organization (WHO), abortion rates are similar in countries where the procedure is legal and in countries where it is not, due to unavailability of modern contraceptives in areas where abortion is illegal.