There are three main types of medical abortion. By far the most common procedure involves insertion of a cannula through a woman's cervix and removing the fetus and placenta using vacuum aspiration. This procedure generally is used in the first trimester (i.e., the first three months after conception) and accounts for about 90% of all medical abortions. In this procedure, which takes about 5 to 10 minutes and can be performed in a physician's office, the woman lies on an examining table with her feet in stirrups. A local anesthetic is administered to numb the woman's cervix. In some cases, a general anesthetic may be used to induce sleep, but this is usually not necessary. The first step in the procedure involves the insertion of a speculum to hold the vaginal walls apart, followed by insertion of a cannula through the dilated cervix. The cannula is connected to a mechanical aspirator. The sucking action of the machine, similar to the device used by dentists to remove excess saliva during dental procedures, removes the contents of the uterus. To insure that the abortion is complete, the physician may insert a spoon-like instrument, called a curette, and checks the walls of the uterus. This ends the procedure.

About 10% of abortions are performed after the 12th week of pregnancy. Two alternative procedures are used with later-term pregnancies. The first is quite similar to the procedure described above, but, because the fetus is larger and more firmly attached to the uterine wall, in addition to using suction the physician inserts a forceps to remove fetal parts that may be too large to be successfully aspirated. The procedure takes up to 30 minutes and may involve the administration of pain medication to the woman. Alternately, in pregnancies that are past the twenty-second week of development, it is possible to induce labor chemically causing the fetus to be expelled through the vaginal opening. Unlike the other procedures, this procedure is generally performed in a hospital. A needle is inserted through the abdominal wall into the uterus and a labor-inducing medication (such as prostaglandin, urea, or saline solution or some combination of these) is injected. Within a few hours, the woman begins labor and the fetus is expelled.

Regardless of the method used, women who have undergone an abortion should be checked for blood pressure and heart rate, and monitored to insure that bleeding and discomfort are limited. One or more follow-up appointments may be arranged several weeks after the abortion to insure that the procedure has been successful and that the woman is healthy. In abortions performed before the 13th week of pregnancy, some follow-up surgery, for example, to remove a blood clot or to repair a tear in the cervix, is needed in only 0.5% of cases. In abortions performed between13 and 24 weeks, complications are somewhat more frequent, in part because of the use of a general anesthesia. The death rate for women who have medical abortions is one in 160,000. By comparison, in full term pregnancies, the death rate is one for every 16,000 successful deliveries.

In the years before abortion was legal, from the late 1800s until the famous Roe v. Wade Supreme Court decision of 1973, more pregnant women died from infections, retained placentas, poisoning, shock, profuse bleeding and other complications brought on by self-induced abortions or abortions performed by unqualified practitioners than from any other single cause. In parts of the world where abortion is still illegal, these remain a leading cause of maternal death. By contrast, today's legal medical abortion is one of the most common and safest surgical procedures in the U.S. Approximately 1.3 million women choose to have a medical abortion performed each year. Major complications and side effects occur in only about 1% of medical abortions. Some women experience menstrual-like cramping during an abortion and for up to an hour afterward. Most women report that this cramping is uncomfortable but not painful. Vaginal bleeding, similar to a menstrual period, generally occurs after an abortion is completed. For the most part, the earlier in pregnancy an abortion is performed, the less likely there will be medical complications.

Despite the limited complications and risks involved, medical abortion is one of the most controversial domestic issues in American society, with anti-abortion and pro-choice supporters embracing diametrically opposed stances on the morality and legality of abortion. Those who oppose abortion, usually on moral or religious grounds, generally maintain that abortion is murder. Additionally, anti-abortion activists argue that there is evidence suggesting that abortion increases the risk that a woman will develop breast cancer, and that women who have abortions tend to experience significant complications in later pregnancies. They also assert that many women casually use abortion as a form of birth control, and that they generally come to regret choosing abortion after it is too late. Finally, they argue that husbands, boyfriends, or parents force many women into having abortions, while others have abortions for very selfish or frivolous reasons.

To express their opposition to abortion, activists have formed local and national organizations that seek to change existing laws allowing abortion, to restrict funding for abortion, or to otherwise limit the capacity of health care providers to perform abortions. Some anti-abortion activists also engage in disturbances at clinics that perform abortion, picketing, blocking the entrances or chaining the doors shut, and interfering with clients seeking to enter clinical buildings. In addition, there has been a steady rise in anti-abortion violence. Many clinics that perform abortions have been subject to vandalism, arson, or bombings. Additionally, the medical staff of clinics and women's reproductive health centers have been threatened, injured, or, ironically (given the pro-life agenda of the anti-abortion movement), murdered in a number of cities. While abortion continues to be a legal procedure, anti-abortion activists have achieved some success. In part due to narrowing access to legal abortions (as well as to improved use of contraception and the aging of the large "baby boomer" population), the number of abortions performed each year declined from a high of 1.4 million in 1990 to 1.27 million in 1994.

People who support a woman's legal right to choose to have an abortion counter all of the assertions made by anti-abortion activists. A recent study published in the New England Journal of Medicine (Jan. 9. 1997), reporting on the largest examination of the alleged linkage between abortion and breast cancer, found no increased risk of breast cancer among women who had abortions during the first 18 weeks of pregnancy. Among the small number of women who have abortions after 18 weeks, the study found a small increase in the rate of breast cancer. Other researchers have found little if any support for the claims of abortion opponents that abortion increases emotional distress in women. Women who report emotional problems after abortion tend to have had similar conditions prior to their abortion. Supporters of legal abortion note that relief is the most common emotion expressed by women following abortion. Contrary to the suggestion that many women are using abortion as a birth control method, it has been found that it is a failure of birth control used at the time of conception that leads to about half of the unwanted pregnancies that end in abortion. One study found that the proportion of women who have abortions because they became pregnant due to condom failure increased from 15% to 32% in recent years. Most women (55%) who have abortions are under 24 years of age (20% are under 20 years of age), and 81% are unmarried (63% have never been married). Many (33%) have incomes below $11,000 a year. Moreover, they represent all major religious traditions, including 16% who describe themselves as born-again Christians and over 30% who report they are Catholic.

For almost all women, the decision to have an abortion is a difficult one. Most women reach the decision to have an abortion because of a lack of money to raise a child or because they feel unready to be a full-time parent or to have additional children. Others make the decision because of a serious medical condition, when they learn that the fetus has severe abnormalities, or because they are in the midst of an overwhelming personal crisis.