Table of Contents
Definition of Abortion Procedure
The end of a pregnancy before the fetus is viable (capable of independent life). Abortion may occur spontaneously (commonly called miscarriage) or be induced to end a pregnancy. In the United States, federal law mandates the availability of induced abortion, and state laws regulate the definition of viability as it applies to induced abortion.
The range of legal viability is 20 weeks to 24 weeks of gestational age. The clinical border for viability is generally 20 weeks or a fetal weight of 500 grams (about 1 pound). It is uncommon for a fetus delivered between 24 and 20 weeks and unlikely for a fetus born before 20 weeks of gestational age to survive. A full-term pregnancy is 42 weeks.
Numerous factors may initiate spontaneous abortion. The most vulnerable period of pregnancy for spontaneous abortion is between 7 and 12 weeks. Doctors believe that most abortions that occur within this early stage of pregnancy occur because the conceived embryo has congenital or chromosomal defects that are not survivable.
About 15 percent of known pregnancies end in spontaneous abortion before the 12th week of pregnancy.
Regardless of the cause and the stage of pregnancy, spontaneous abortion is often a traumatic loss for the woman and her partner.
An induced abortion is a procedure a woman chooses to undergo to end a pregnancy and may be therapeutic (medically necessary for the woman’s health or because the fetus has known, nonsurvivable defects such as anencephaly) or elective termination of pregnancy.
An induced abortion may be a surgical procedure called dilation and evacuation (D&E), performed under anesthesia in a hospital operating room or in an ambulatory surgical facility, in which the doctor dilates the cervix and withdraws the contents of the uterus via suction (also called vacuum aspiration abortion).
Before seven weeks an induced abortion may be a medical procedure, brought about by taking medications such as mifepristone (RU486), methotrexate, or misoprostol. These drugs, called abortifacients, prevent cell division (methotrexate, a chemotherapy drug used to treat cancer) or implantation, or initiate uterine contractions (mifepristone and misoprostol).
Uncontrolled bleeding (hemorrhage) and infection are risks with either spontaneous or induced abortion. The abortion may be incomplete (some of the contents of conception remain in the uterus), causing persistent or occasionally heavy bleeding.
Persistent or heavy bleeding often requires dilation and curettage (D&C), a surgical procedure in which the doctor dilates the cervix and uses a curette to gently scrape the interior walls of the uterus. Undiagnosed gonorrhea and chlamydia are the most common causes of postabortion infection.
Infection requires treatment with antibiotic medications. Either bleeding or infection may be life threatening; both require immediate medical evaluation and appropriate treatment. Rarely, abortion results in complications that can affect future fertility.
Abortion, whether spontaneous or induced, is often an emotional experience for the woman and her partner. Guilt, sadness, and anger are common feelings that may persist for some time or reemerge years later. Induced abortion often has additional religious or philosophical implications.
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