Induced abortion is a method for terminating a pregnancy.
Two general categories exist: medical abortion and surgical abortion.
With medical abortion, the patient is given either methotrexate (stops rapidly growing cells), or mifepristone (blocks progesterone, leading to shedding of the uterine lining). Then, misoprostol (prostaglandin that causes the uterus to contract) is given to expel the pregnancy. The whole procedure can take a week or two to complete.
Medical abortion is usually restricted to those within 63 days of their last menstrual period (9 weeks gestational age). It frequently causes significant cramping, abdominal pain, nausea, vomiting and diarrhea. However, it usually avoids surgery and anesthesia, and the abortion is completed at home, in private.
Methotrexate is about 90% effective in terminating early pregnancies. Mifepristone (RU486) is about 95% effective in terminating pregnancy. As both are potentially teratogenic, surgical termination is usually recommended should they be unsuccessful in causing the abortion.
Complications of medical abortion include the usual risks of incomplete abortion (infection, bleeding), and the occasional side-effect to the medications.
Surgical abortion is usually achieved by dilating the cervix, then inserting instruments through the cervix and into the uterus to remove the pregnancy. This is variously known as D&C (dilatation and curettage), D&E (dilatation and evacuation) and sometimes MVA (manual vacuum aspiration).
The procedure is the same as would be used for terminating a missed abortion or incomplete abortion. This can be performed with relatively little risk up to 14 weeks gestation, and somewhat greater risk up to 24 weeks gestation.
Surgical abortion is highly effective, in excess of 99%. Its advantages include the immediate termination of the pregnancy in a controlled setting with effective anesthesia.
Risks of surgical abortion include the usual surgical risks of bleeding, infection, anesthesia complications and injury to adjacent structures. Serious complications are uncommon. Subsequent fertility does not seem to be affected, unless an individual has had many surgical terminations.