Abortion
From Wikipedia, the free encyclopedia
| Induced abortion |
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| Classification and external resources |
Bas-relief at Angkor Wat, Cambodia, c. 1150, depicting a demon inducing an abortion by pounding the abdomen of a pregnant woman with a pestle. |
ICD-10 | O04. |
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| ICD-9 | 779.6 |
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| DiseasesDB | 4153 |
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| MedlinePlus | 002912 |
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| eMedicine | article/252560 |
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Abortion is the termination of a pregnancy by the removal or expulsion from the uterus of a fetusor embryo, resulting in or caused by its death. An abortion can occur spontaneously due tocomplications during pregnancy or can be induced, in humans and other species. In the context of human pregnancies, an abortion induced to preserve the health of the gravida (pregnant female) is termed a therapeutic abortion, while an abortion induced for any other reason is termed an elective abortion. The term abortion most commonly refers to the induced abortion of a human pregnancy, while spontaneous abortions are usually termed miscarriages.
Worldwide 42 million abortions are estimated to take place annually with 22 million of these occurring safely and 20 million unsafely. While maternal mortality seldom results from safe abortions, unsafe abortions result in 70,000 deaths and 5 million disabilities per year.One of the main determinants of the availability of safe abortions is the legality of the procedure. Forty percent of the world's women are able to access therapeutic and elective abortions within gestational limits. The frequency of abortions is, however, similar whether or not access is restricted.
Abortion has a long history and has been induced by various methods including herbalabortifacients, the use of sharpened tools, physical trauma, and other traditional methods. Contemporary medicine utilizes medications and surgical procedures to induce abortion. Thelegality, prevalence, and cultural views on abortion vary substantially around the world. In many parts of the world there is prominent and divisive public controversy over the ethical and legal issues of abortion. Abortion and abortion-related issues feature prominently in the national politics in many nations, often involving the opposing pro-life and pro-choice worldwide social movements (both self-named). Incidence of abortion has declined worldwide, as access to family planning education and contraceptive services has increased.
Types
A 10-week-old fetus removed via a therapeutic abortion from a 44-year-old female diagnosed with early-stage uterine cancer. The uterus (womb), included the fetus.
Spontaneous
Miscarriage
Spontaneous abortion (also known as miscarriage) is the expulsion of an embryo or fetus due to accidental trauma or natural causes before approximately the 22nd week of gestation; the definition by gestational age varies by country. Most miscarriages are due to incorrect replication of chromosomes; they can also be caused by environmental factors. A pregnancy that ends before 37 weeks of gestation resulting in a live-born infant is known as a "premature birth". When a fetus dies in utero after about 22 weeks, or during delivery, it is usually termed "stillborn". Premature births and stillbirths are generally not considered to be miscarriages although usage of these terms can sometimes overlap.
Between 10% and 50% of pregnancies end in clinically apparent miscarriage, depending upon the age and health of the pregnant woman. Most miscarriages occur very early in pregnancy, in most cases, they occur so early in the pregnancy that the woman is not even aware that she was pregnant. One study testing hormones for ovulation and pregnancy found that 61.9% of conceptuses were lost prior to 12 weeks, and 91.7% of these losses occurred subclinically, without the knowledge of the once pregnant woman.
The risk of spontaneous abortion decreases sharply after the 10th week from the last menstrual period (LMP). One study of 232 pregnant women showed "virtually complete [pregnancy loss] by the end of the embryonic period" (10 weeks LMP) with a pregnancy loss rate of only 2 percent after 8.5 weeks LMP.
The most common cause of spontaneous abortion during the first trimester is chromosomal abnormalities of the embryo/fetus, accounting for at least 50% of sampled early pregnancy losses.Other causes include vascular disease (such as lupus), diabetes, other hormonal problems, infection, and abnormalities of the uterus. Advancing maternal age and a patient history of previous spontaneous abortions are the two leading factors associated with a greater risk of spontaneous abortion. A spontaneous abortion can also be caused by accidental trauma; intentional trauma or stress to cause miscarriage is considered induced abortion or feticide.
Induced
A pregnancy can be intentionally aborted in many ways. The manner selected depends chiefly upon the gestational age of the embryo or fetus, which increases in size as it ages.Specific procedures may also be selected due to legality, regional availability, and doctor-patient preference. Reasons for procuring induced abortions are typically characterized as either therapeutic or elective. An abortion is medically referred to as therapeutic when it is performed to:
save the life of the pregnant woman;
preserve the woman's physical or mental health;
terminate pregnancy that would result in a child born with a congenital disorder that would be fatal or associated with significant morbidity; or
selectively reduce the number of fetuses to lessen health risks associated with multiple pregnancy.
An abortion is referred to as elective when it is performed at the request of the woman "for reasons other than maternal health or fetal disease."
Methods
Gestational age may determine which abortion methods are practiced.
Medical abortion
"Medical abortions" are non-surgical abortions that use pharmaceutical drugs. Medical abortions comprise 10% of all abortions in the United States and Europe.[citation needed] Combined regimens include methotrexate or mifepristone, followed by a prostaglandin (either misoprostol or gemeprost: misoprostol is used in the U.S.; gemeprost is used in the UK and Sweden.) When used within 49 days gestation, approximately 92% of women undergoing medical abortion with a combined regimen completed it without surgical intervention.Misoprostol can be used alone, but has a lower efficacy rate than combined regimens. In cases of failure of medical abortion, vacuum or manual aspiration is used to complete the abortion surgically.
Surgical
A vacuum aspiration abortion at eight weeks gestational age (six weeks after fertilization).
1: Amniotic sac
2: Embryo
3: Uterine lining
4: Speculum
5: Vacurette
6: Attached to a suction pump
In the first 12 weeks, suction-aspiration or vacuum abortion is the most common method. Manual vacuum aspiration (MVA) abortion consists of removing the fetus or embryo, placenta and membranes by suction using a manual syringe, while electric vacuum aspiration (EVA) abortion uses an electric pump. These techniques are comparable, and differ in the mechanism used to apply suction, how early in pregnancy they can be used, and whether cervical dilation is necessary. MVA, also known as "mini-suction" and "menstrual extraction", can be used in very early pregnancy, and does not require cervical dilation. Surgical techniques are sometimes referred to as 'Suction (or surgical) Termination Of Pregnancy' (STOP). From the 15th week until approximately the 26th, 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), the second most common method of abortion, is a standard gynecological procedure performed for a variety of reasons, including examination of the uterine lining for possible malignancy, investigation of abnormal bleeding, and abortion. Curettage refers to cleaning the walls of the uterus with a curette. The World Health Organization recommends this procedure, also called sharp curettage, only when MVA is unavailable.
Other techniques must be used to induce abortion in the second trimester. Premature delivery can be induced with prostaglandin; this can be coupled with injecting the amniotic fluid with hypertonic solutions containing saline or urea. After the 16th week of gestation, abortions can be induced by intact dilation and extraction (IDX) (also called intrauterine cranial decompression), which requires surgical decompression of the fetus's head before evacuation. IDX is sometimes called "partial-birth abortion," which has been federally banned in the United States. A hysterotomy abortion is a procedure similar to a caesarean section and is performed under general anesthesia. It requires a smaller incision than a caesarean section and is used during later stages of pregnancy.
From the 20th to 23rd week of gestation, an injection to stop the fetal heart may be used as the first phase of the surgical abortion procedure to ensure that the fetus is not born alive.
Other methods
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 by causing trauma to the abdomen. The degree of force, 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 Southeast Asia, there is an ancient tradition of attempting abortion through forceful abdominal massage. One of the bas reliefs decorating the temple of Angkor Wat in Cambodia depicts a demon performing such an abortion upon a woman who has been sent to the underworld.
Reported methods of unsafe, self-induced abortion include misuse of misoprostol, and insertion of non-surgical implements such as knitting needles and clothes hangers into the uterus. These methods are rarely seen in developed countries where surgical abortion is legal and available.
Health risks
See also: Health risks of unsafe abortion
Abortion, when legally performed in developed countries, is among the safest procedures in medicine. In such settings, risk of maternal death is between 0.2–1.2 per 100,000 procedures. In comparison, by 1996, mortality from childbirth in developed countries was 11 times greater. Unsafe abortions (defined by the World Health Organization as those performed by unskilled individuals, with hazardous equipment, or in unsanitary facilities) carry a high risk of maternal death and other complications. For unsafe procedures, the mortality rate has been estimated at 367 per 100,000.
Physical health
Surgical abortion methods, like most minimally invasive procedures, carry a small potential for serious complications.
Surgical abortion is generally safe and the rate of major complications is low but varies depending on how far pregnancy has progressed and the surgical method used.Concerning gestational age, incidence of major complications is highest after 20 weeks of gestation and lowest before the 8th week.With more advanced gestation there is a higher risk of uterine perforation and retained products of conception,and specific procedures like dilation and evacuation may be required.
Concerning the methods used, general incidence of major complications for surgical abortion varies from lower for suction curettage, to higher for saline instillation.Possible complications include hemorrhage, incomplete abortion, uterine or pelvic infection, ongoing intrauterine pregnancy, misdiagnosed/unrecognized ectopic pregnancy, hematometra (in the uterus), uterine perforation and cervical laceration. Use of general anesthesia increases the risk of complications because it relaxes uterine musculature making it easier to perforate.
In the first trimester, health risks associated with medical abortion are generally considered no greater than for surgical abortion.
Abortion and mental health
No scientific research has demonstrated that abortion is a cause of poor mental health in the general population. However there are groups of women who may be at higher risk of coping with problems and distress following abortion. Some factors in a woman's life, such as emotional attachment to the pregnancy, lack of social support, pre-existing psychiatric illness, and conservative views on abortion increase the likelihood of experiencing negative feelings after an abortion. The American Psychological Association (APA) concluded that abortion does not lead to increased mental health problems.
Some proposed negative psychological effects of abortion have been referred to by anti-abortion advocates as a separate condition called "post-abortion syndrome." However, the existence of "post-abortion syndrome" is not recognized by any medical or psychological organization.
Incidence
The number of abortions performed worldwide has deceased between 1995 and 2003 from 45.6 million to 41.6 million (a decrease from 35 to 29 per 1000 women between 15 and 44 years of age). The greatest decrease has occurred in the developed world with a decrease from 39 to 26 per 1000 women in comparison to the developing world which had a decrease from 34 to 29 per 1000 women. Of these approximately 42 million abortions 22 million occurred safely and 20 million unsafely.
The incidence and reasons for induced abortion vary regionally. Some countries, such as Belgium (11.2 per 1000 known pregnancies) and the Netherlands (10.6 per 1000), had a comparatively low rate of induced abortion, while others like Russia (62.6 per 1000) and Vietnam (43.7 per 1000) had a high rate. The world ratio was 26 induced abortions per 1000 known pregnancies (excluding miscarriages and stillbirths).
By gestational age and method
Histogram of abortions by gestational age in England and Wales during 2004. Average is 9.5 weeks. (left) Abortion in the United States by gestational age, 2004. (Data source: Centers for Disease Control and Prevention) (right)
Abortion rates also vary depending on the stage of pregnancy and the method practiced. In 2003, from data collected in those areas of the United States that sufficiently reported gestational age, it was found that 88.2% of abortions were conducted at or prior to 12 weeks, 10.4% from 13 to 20 weeks, and 1.4% at or after 21 weeks. 90.9% of these were classified as having been done by "curettage" (suction-aspiration, Dilation and curettage, Dilation and evacuation), 7.7% by "medical" means (mifepristone), 0.4% by "intrauterine instillation" (saline or prostaglandin), and 1.0% by "other" (including hysterotomy and hysterectomy). The Guttmacher Institute estimated there were 2,200 intact dilation and extraction procedures in the U.S. during 2000; this accounts for 0.17% of the total number of abortions performed that year.Similarly, in England and Wales in 2006, 89% of terminations occurred at or under 12 weeks, 9% between 13 to 19 weeks, and 1.5% at or over 20 weeks. 64% of those reported were by vacuum aspiration, 6% by D&E, and 30% were medical. Later abortions are more common in China, India, and other developing countries than in developed countries.
By personal and social factors
A bar chart depicting selected data from the 1998 AGI meta-study on the reasons women stated for having an abortion.
A 1998 aggregated study, from 27 countries, on the reasons women seek to terminate their pregnancies concluded that common factors cited to have influenced the abortion decision were: desire to delay or end childbearing, concern over the interruption of work or education, issues of financial or relationship stability, and perceived immaturity.A 2004 study in which American women at clinics answered a questionnaire yielded similar results. In Finland and the United States, concern for the health risks posed by pregnancy in individual cases was not a factor commonly given; however, in Bangladesh, India, and Kenya health concerns were cited by women more frequently as reasons for having an abortion. 1% of women in the 2004 survey-based U.S. study became pregnant as a result of rape and 0.5% as a result of incest. Another American study in 2002 concluded that 54% of women who had an abortion were using a form of contraception at the time of becoming pregnant while 46% were not. Inconsistent use was reported by 49% of those using condoms and 76% of those using the combined oral contraceptive pill; 42% of those using condoms reported failure through slipping or breakage.The Guttmacher Institute estimated that "most abortions in the United States are obtained by minority women" because minority women "have much higher rates of unintended pregnancy."
Some abortions are undergone as the result of societal pressures. These might include the stigmatization of disabled people, preference for children of a specific sex, disapproval of single motherhood, insufficient economic support for families, lack of access to or rejection of contraceptive methods, or efforts toward population control (such as China's one-child policy). These factors can sometimes result in compulsory abortion or sex-selective abortion.
Unsafe abortion
Soviet poster circa 1925, promoting hospital abortions. Title translation: "Abortions performed by either trained or self-taught midwives not only maim the woman, they also often lead to death."
Women seeking to terminate their pregnancies sometimes resort to unsafe methods, particularly where and when access to legal abortion is restricted. The World Health Organization (WHO) 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." Unsafe abortions are sometimes known colloquially as "back-alley" abortions. They may be performed by the woman herself, another person without medical training, or a professional health provider operating in sub-standard conditions. Unsafe abortion remains a public health concern due to the higher incidence and severity of its associated complications, such as incomplete abortion, sepsis, hemorrhage, and damage to internal organs. It is estimated that 20 million unsafe abortions occur around the world annually and that 70,000 of these result in the woman's death.Complications of unsafe abortion are said to account, globally, for approximately 13% of all maternal mortalities, with regional estimates including 12% in Asia, 25% in Latin America, and 13% in sub-Saharan Africa.Although the global rate of abortion declined from 45.6 million in 1995 to 41.6 million in 2003, unsafe procedures still accounted for 48% of all abortions performed in 2003.Health education, access to family planning, and improvements in health care during and after abortion have been proposed to address this phenomenon.
History
"French Periodical Pills." An example of a clandestine advertisement published in an 1845 edition of the Boston Daily Times.
History of abortion
Induced abortion can be traced to ancient times.There is evidence to suggest that, historically, pregnancies were terminated through a number of methods, including the administration of abortifacient herbs, the use of sharpened implements, the application of abdominal pressure, and other techniques.
The Hippocratic Oath, the chief statement of medical ethics for Hippocratic physicians in Ancient Greece, forbade doctors from helping to procure an abortion by pessary. Soranus, a second-century Greek physician, suggested in his work Gynaecology that women wishing to abort their pregnancies should engage in energetic exercise, energetic jumping, carrying heavy objects, and riding animals. He also prescribed a number of recipes for herbal baths, pessaries, and bloodletting, but advised against the use of sharp instruments to induce miscarriage due to the risk of organ perforation.It is also believed that, in addition to using it as a contraceptive, the ancient Greeks relied upon silphium as an abortifacient. Such folk remedies, however, varied in effectiveness and were not without risk. Tansy and pennyroyal, for example, are two poisonous herbs with serious side effects that have at times been used to terminate pregnancy.
During the medieval period, physicians in the Islamic world documented detailed and extensive lists of birth control practices, including the use of abortifacients, commenting on their effectiveness and prevalence.They listed many different birth control substances in their medical encyclopedias, such as Avicenna listing 20 in The Canon of Medicine (1025) and Muhammad ibn Zakariya ar-Razi listing 176 in his Hawi (10th century). This was unparalleled in European medicine until the 19th century.
During the Middle Ages, abortion was tolerated and there were no laws against it.A medieval female physician, Trotula of Salerno, administered a number of remedies for the “retention of menstrua,” which was sometimes a code for early abortifacients. Pope Sixtus V (1585–90) is noted as the first Pope to declare that abortion is homicide regardless of the stage of pregnancy.Abortion in the 19th century continued, despite bans in both the United Kingdom and the United States, as the disguised, but nonetheless open, advertisement of services in the Victorian era suggests.
In the 20th century the Soviet Union (1919), Iceland (1935) and Sweden (1938) were among the first countries to legalize certain or all forms of abortion. In 1935 Nazi Germany, a law was passed permitting abortions for those deemed "hereditarily ill," while women considered of German stock were specifically prohibited from having abortions.
Society and culture
Pro-choice activists near the Washington Monument at the March for Women's Lives in 2004. (left) Pro-life activists near the Washington Monument at the annual 2009 March for Life in Washington, DC. (right)
Main article: Abortion debate
In the history of abortion, induced abortion has been the source of considerable debate, controversy, and activism. An individual's position on the complex ethical, moral, philosophical, biological, and legal issues is often related to his or her value system. The main positions are one that argues in favor of access to abortion and one argues against access to abortion. Opinions of abortion may be described as being a combination of beliefs on its morality, and beliefs on the responsibility, ethical scope, and proper extent of governmental authorities in public policy. Religious ethics also has an influence upon both personal opinion and the greater debate over abortion (see religion and abortion).
Abortion debates, especially pertaining to abortion laws, are often spearheaded by groups advocating one of these two positions. In the United States, those in favor of greater legal restrictions on, or even complete prohibition of abortion, most often describe themselves as pro-life while those against legal restrictions on abortion describe themselves as pro-choice. Generally, the former position argues that a human fetus is a human being with a right to live making abortion tantamount to murder. The latter position argues that a woman has certain reproductive rights, especially the choice whether or not to carry a pregnancy to term.
In both public and private debate, arguments presented in favor of or against abortion access focus on either the moral permissibility of an induced abortion, or justification of laws permitting or restricting abortion.
Debate also focuses on whether the pregnant woman should have to notify and/or have the consent of others in distinct cases: a minor, her parents; a legally married or common-law wife, her husband; or a pregnant woman, the biological father. In a 2003 Gallup poll in the United States, 79% of male and 67% of female respondents were in favor of legalized mandatory spousal notification; overall support was 72% with 26% opposed.
Abortion law
Main article: Abortion law
Reproductive rights
International status of abortion law:
Legal on request
Legal for maternal life, health, mental health, rape, fetal defects, and/or socioeconomic factors
Legal for or illegal with exception for maternal life, health, mental health, rape, and/or fetal defects
Illegal with exception for maternal life, health, mental health and/or rape
Illegal with exception for maternal life, health, and/or mental health
Illegal with no exceptions
No information
Vertical stripes (various colours): Illegal but unenforced
Before the scientific discovery in the nineteenth century that human development begins at fertilization, English common law forbade abortions after "quickening", that is, after "an infant is able to stir in the mother's womb." There was also an earlier period in England when abortion was prohibited "if the foetus is already formed" but not yet quickened. Both pre- and post-quickening abortions were criminalized by Lord Ellenborough's Act in 1803. In 1861, the Parliament of the United Kingdom passed the Offences against the Person Act 1861, which continued to outlaw abortion and served as a model for similar prohibitions in some other nations.
The Soviet Union, with legislation in 1920, and Iceland, with legislation in 1935, were two of the first countries to generally allow abortion. The second half of the 20th century saw the liberalization of abortion laws in other countries. The Abortion Act 1967 allowed abortion for limited reasons in the United Kingdom (except Northern Ireland). In the 1973 case, Roe v. Wade, the United States Supreme Court struck down state laws banning abortion, ruling that such laws violated an implied right to privacy in the United States Constitution. The Supreme Court of Canada, similarly, in the case of R. v. Morgentaler, discarded its criminal code regarding abortion in 1988, after ruling that such restrictions violated the security of person guaranteed to women under the Canadian Charter of Rights and Freedoms. Canada later struck down provincial regulations of abortion in the case of R. v. Morgentaler (1993). By contrast, abortion in Ireland was affected by the addition of an amendment to the Irish Constitution in 1983 by popular referendum, recognizing "the right to life of the unborn".
Current laws pertaining to abortion are diverse. Religious, moral, and cultural sensibilities continue to influence abortion laws throughout the world. The right to life, the right to liberty, the right to security of person, and the right to reproductive health are major issues of human rights that are sometimes used as justification for the existence or absence of laws controlling abortion. Many countries in which abortion is legal require that certain criteria be met in order for an abortion to be obtained, often, but not always, using a trimester-based system to regulate the window of legality:
In the United States, some states impose a 24-hour waiting period before the procedure, prescribe the distribution of information on fetal development, or require that parents be contacted if their minor daughter requests an abortion.
In the United Kingdom, as in some other countries, two doctors must first certify that an abortion is medically or socially necessary before it can be performed.
In Canada, a similar requirement was rejected as unconstitutional in 1988.
Other countries, in which abortion is normally illegal, will allow one to be performed in the case of rape, incest, or danger to the pregnant woman's life or health.
A few nations ban abortion entirely: Chile, El Salvador, Malta, and Nicaragua, with consequent rises in maternal death directly and indirectly due to pregnancy. However, in 2006, the Chilean government began the free distribution of emergency contraception.
In Bangladesh, abortion is illegal, but the government has long supported a network of "menstrual regulation clinics", where menstrual extraction (manual vacuum aspiration) can be performed as menstrual hygiene.
In places where abortion is illegal or carries heavy social stigma, pregnant women may engage in medical tourism and travel to countries where they can terminate their pregnancies. Women without the means to travel can resort to providers of illegal abortions or try to do it themselves.
In the US, about 8% of abortions are performed on women who travel from another state.However, that is driven at least partly by differing limits on abortion according to gestational age or the scarcity of doctors trained and willing to do later abortions.
Sex-selective abortion
Sonography and amniocentesis allow parents to determine sex before childbirth. The development of this technology has led to sex-selective abortion, or the targeted termination of female fetuses.
It is suggested that sex-selective abortion might be partially responsible for the noticeable 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 abortion used to limit female births has been reported in China, Taiwan, South Korea, and India.
In India, the economic role of men, the costs associated with dowries, and a common Indian tradition which dictates that funeral rites must be performed by a male relative have led to a cultural preference for sons. The widespread availability of diagnostic testing, during the 1970s and '80s, led 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, led to an increased disparity in the sex ratio as parents attempted to circumvent the law through sex-selective abortion or the abandonment of unwanted daughters. Sex-selective abortion might be an influence on 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.
In other animals
Further information: Miscarriage#In other animals
Spontaneous abortion occurs in various animals. For example, in sheep, it may be caused by crowding through doors, or being chased by dogs. In cows, abortion may be caused by contagious disease, such as Brucellosis or Campylobacter, but can often be controlled by vaccination. Additionally, many other diseases are known to increase the risk of miscarriage in humans and other animals.[citation needed]
Abortion may also be induced in animals, in the context of animal husbandry. For example, abortion may be induced in mares that have been mated improperly, or that have been purchased by owners who did not realize the mares were pregnant, or that are pregnant with twin foals.
Feticide can occur in horses and zebras due to male harassment of pregnant mares or forced copulation, although the frequency in the wild has been questioned. Male Gray langur monkeys may attack females following male takeover, causing miscarriage.
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