An abortion is the termination of a pregnancy associated with the death of an embryo or a fetus. This can occur spontaneously, in the form of a miscarriage, or be intentionally induced through chemical, surgical, or other means. All mammalian pregnancies can be aborted; however, this article focuses exclusively on the abortion of human pregnancy.
There have been various methods of inducing an abortion throughout the centuries. In the 20th century, the ethics and morality of abortions became the subject of intense political debate in many areas of the world.
A pregnancy can be intentionally aborted in a number of ways. The manner selected depends chiefly upon the gestational age of the fetus, in addition to the legality, regional availability, and/or doctor-patient preference for specific procedures.
In the first fifteen weeks, suction-aspiration or vacuum abortion are the most common methods, replacing the more risky dilation and curettage (D & C). Manual vacuum aspiration, or MVA abortion, consists of removing the fetus or embryo by suction using a manual syringe, while the Electric vacuum aspiration or EVA abortion method uses an electric pump. From the fifteenth week up until around the eighteenth week, a surgical dilation and evacuation (D & E) is used. D & E consists of opening the cervix of the uterus and emptying it using surgical instruments and suction.
Dilation and curettage (D & C) is a standard gynaecological procedure performed for a variety of reasons, such as examination. Curettage refers to the cleaning of the walls of the uterus with a curette. Dilation and suction curettage consists of emptying the uterus by suction instead of with a curette.
Other techniques must be used to induce abortion in the third trimester. Premature delivery can be induced with prostaglandin; this can be coupled with injecting the amniotic fluid with caustic solutions containing saline or urea. Very late abortions can be brought about by intact dilation and extraction (intact D & X), which requires the surgical decompression of the fetus's head before evacuation, and is sometimes termed "partial-birth abortion." A hysterotomy abortion, similar to a caesarian section but resulting in a terminated fetus, can also be used at late stages of pregnancy. It can be performed vaginally, with an incision just above the cervix, in the late mid-trimester.
Effective in the first trimester of pregnancy, chemical, or non-surgical abortions comprise 10% of all abortions in the United States and Europe. The process begins with the administration of either methotrexate or mifepristone, followed by misoprostol. While misoprostol may also be used alone to induce abortion, the need for surgical intervention is slightly elevated to about 10%, compared to the 8% when medications are combined. When surgical intervention is necessary, primarily vacuum uterine aspiration is used.
Other means of abortion
Historically, a number of herbs reputed to possess abortifacient properties have been used in folk medicine: tansy, pennyroyal, black cohosh, and the now-extinct silphium (see history of abortion). The use of herbs in such a manner can cause serious — even lethal — side effects, such as multiple organ failure, and is not recommended by physicians.
Abortion is sometimes attempted through means of trauma to the abdomen. The degree of force applied, if severe, can cause serious internal injuries without necessarily succeeding in inducing miscarriage. Both accidental and deliberate abortions of this kind can be subject to criminal liability in many countries. In Burma, Indonesia, Malaysia, the Phillipines, and Thailand, there is an ancient tradition of attempting abortion through forceful abdominal massage.
Where and when access to safe abortion has been barred, due to explicit sanctions or general unavailability, women seeking to terminate their pregnancies have sometimes resorted to unsafe methods.
"Back-alley abortion" is a slang term for any abortion not practiced under ideal conditions of sanitation and professionalism. The World Health Organization defines an unsafe abortion as being, "a procedure...carried out by persons lacking the necessary skills or in an environment that does not conform to minimal medical standards, or both." This includes a person without medical training, a professional health provider operating in sub-standard conditions, or the woman herself. A few reported methods of such self-induced abortion are the misuse of the ulcer drug Misoprostol, abdominal massage and trauma, and the insertion of non-surgical implements such as knitting needles and clothes hangers into the uterus.
Unsafe abortion remains a concern today due to the higher incidence and severity of its associated complications, such as incomplete abortion, sepsis, haemorrhage, and damage to internal organs. The World Health Organization estimates that 19 million unsafe abortions occur around the world annually and that 68,000 of these result in death.
Sex-selective abortion (infanticide)
The advent of both ultrasound and amniocentesis has allowed parents to determine sex before birth. This has lead to the occurrence of sex-selective abortion or the targeted termination of a fetus based upon its gender.
It is suggested that sex-selective abortion might be partially reponsible for the noticable disparities between the birth rates of male and female children in some places. The preference for male children is reported in many areas of Asia, and the use of abortion as a deterrent to female birth has been reported in Mainland China, Taiwan, South Korea, and India.
In India, the economic role of men, the costs associated with dowries, and a Hindu tradition which dicates that funeral rites must be performed by a male relative have lead to a cultural preference for sons. The widespread availability of diagnostic testing, during the 1970s and '80s, lead to advertisements for services which read, "Invest 500 rupees [for a sex test] now, save 50,000 rupees [for a dowry] later." In 1991, the male-to-female sex ratio in India was skewed from its biological norm of 105 to 100, to an average of 108 to 100. Researchers have asserted that between 1985 and 2005 as many as 10 million female fetuses may have been selectively aborted. The Indian government passed an official ban of pre-natal sex screening in 1994 and moved to pass a complete ban of sex-selective abortion in 2002.
In the People's Republic of China, there is also a historic son preference. The implementation of the one-child policy in 1979, in response to population concerns, lead to an increased disparities in the sex ratio as parents attempted to circumvent the law through sex-selective abortion or the abandoment of unwanted daughters. Sex-selective abortion might a part of what is behind the shift from the baseline male-to-female birth rate to an elevated national rate of 117:100 reported in 2002. The trend was more pronounced in rural regions: as high as 130:100 in Guangdong and 135:100 in Hainan. A ban upon the practice of sex-selective abortion was enacted in 2003.