An induced abortion is the intentional termination of a pregnancy. The procedure removes a fetus and placenta from a woman’s uterus. The vast majority of abortions performed in the United States are accomplished through surgery, but recent advances have also made abortion possible through medication.

In 1973, the landmark Roe v. Wade Supreme Court ruling stated that women in the United States have a constitutionally protected right to have an abortion during the early stages of pregnancy. The court ruling guaranteed that unrestricted abortion would be available to all women before the viability of the fetus, which is the time when the fetus can exist on its own outside the uterus.

A later Supreme Court ruling gave states the right to restrict abortions as long as it does not create an “undue burden” for women seeking abortion. In the United States, federal law had prohibited any restrictions on abortion during the first trimester of pregnancy until a recent law was passed in South Dakota in February 2006. This is the only state where any abortions had become prohibited in an attempt to counteract the previous federal ruling. Later that year, however, South Dakota voters overturned their state’s abortion ban. There was an effort to reintroduce the South Dakota abortion law in January 2007 with provisions that would allow abortion for rape and incest victims, but the bill was once again overturned the following month. During the second trimester, states may regulate abortion services, but only in regard to preserving a woman’s health.

Abortions may be performed for several reasons. Most often, abortions are performed because a woman does not wish to be pregnant. In the majority of cases, such abortions are performed to terminate a pregnancy after a woman fails to use contraception or the method of birth control has failed. Abortions are also performed to terminate pregnancies that are the result of acts of rape or incest, to prevent the birth of a child with birth defects or because a woman’s health is endangered by the pregnancy.

According to statistics released in 2006 by the Centers for Disease Control and Prevention (CDC), there were approximately 848,163 legal abortions performed in the United States in 2003. This number represents a 0.7 percent decrease from the number of abortions in 2002. Abortion rates have declined over time due to a number of factors, such as fewer cases of unintended pregnancies and more restricted laws for adolescents.

The majority of reported abortions occurred in unmarried women under the age of 25 years. Approximately 49 percent of pregnancies in the United States are unplanned, and one-half of these are terminated with abortions, according to the CDC. This represents 24 percent of all pregnancies, excluding those that end in miscarriages.

There are two principal types of elective abortions performed in the United States. They include surgical abortions, which make up the vast majority of abortions in the United States, and nonsurgical abortions.

In surgical abortions, the cervical canal is dilated (enlarged) and a hollow tube is inserted into the uterus. A vacuum machine is then used to suction the tissues of the fetus and placenta from the uterus. In cases of more advanced pregnancy, forceps (instrument resembling pincers or tongs used for extracting tissue) may be used to remove the fetus, and the uterus may be gently scraped.

Surgical abortions can be performed in several different ways. The choice of technique often depends on how far along the pregnancy is at the time of the abortion. For example:

• Six to 12 weeks. These abortions are often performed while the woman is awake. In most cases, the woman has the option of being sedated by medications, or having an injection of local anesthetic that numbs her cervix.
  
  
• More than 12 weeks. These abortions are usually, but not always, performed while the woman is under general anesthesia, which means she will be asleep during the procedure.

Nonsurgical methods, which include medication, interfere with the development of the placenta and force the uterus to contract, which eventually causes its contents to be expelled. These methods can be used in a pregnancy of 16 weeks or more. Newer protocols for nonsurgical or medical abortions can be used through the first 60 days of a pregnancy.

Almost 90 percent of abortions occur in the first trimester, according to the Alan Guttmacher Institute, a private, nonprofit organization that focuses on sexual and reproductive health research, policy analysis and public education. Fewer than 2 percent are performed after 20 weeks of pregnancy, and just 0.08 percent are performed after 24 weeks.

Controversy has grown over a rarely performed procedure commonly known as partial-birth abortion (clinically referred to as intact dilation and extraction). In this procedure, the physician delivers a baby to the point where only the head remains inside the womb. The physician then punctures the back of the skull and removes the brain before completing delivery. This procedure was banned in 2003. A year later the ban was declared unconstitutional and was heavily appealed until April 2007 when the Supreme Court upheld the banning of partial-birth abortions.

Abortion remains an intensely controversial issue in the United States. Currently, 28 U.S. states require women who want to have an abortion to undergo counseling prior to the procedure, and 24 states require women to wait a specified period of time, usually 24 hours, between the time they receive the counseling and time the procedure is performed. During abortion counseling, women typically receive information to discourage them from having the procedure (e.g., health risks, mental health consequences). As a result, women who consider having this procedure may want to seek outside support from sympathetic family and friends or support groups.