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Tuesday, September 21, 2021

Abortion

From Wikipedia, the free encyclopedia

Abortion
Other namesInduced miscarriage, termination of pregnancy
SpecialtyObstetrics and gynecology
ICD-10-PCSO04
ICD-9-CM779.6
MeSHD000028
MedlinePlus007382

Abortion is the termination of a pregnancy by removal or expulsion of an embryo or fetus. An abortion that occurs without intervention is known as a miscarriage or "spontaneous abortion" and occurs in approximately 30% to 40% of pregnancies. When deliberate steps are taken to end a pregnancy, it is called an induced abortion, or less frequently "induced miscarriage". The unmodified word abortion generally refers to an induced abortion.

When properly done, abortion is one of the safest procedures in medicine, but unsafe abortion is a major cause of maternal death, especially in the developing world, while making safe abortion legal and accessible reduces maternal deaths. It is safer than childbirth, which has a 14 times higher risk of death in the United States.

Modern methods use medication or surgery for abortions. The drug mifepristone in combination with prostaglandin appears to be as safe and effective as surgery during the first and second trimester of pregnancy. The most common surgical technique involves dilating the cervix and using a suction device. Birth control, such as the pill or intrauterine devices, can be used immediately following abortion. When performed legally and safely on a woman who desires it, induced abortions do not increase the risk of long-term mental or physical problems. In contrast, unsafe abortions (those performed by unskilled individuals, with hazardous equipment, or in unsanitary facilities) cause 47,000 deaths and 5 million hospital admissions each year. The World Health Organization states that "access to legal, safe and comprehensive abortion care, including post-abortion care, is essential for the attainment of the highest possible level of sexual and reproductive health".

Around 56 million abortions are performed each year in the world, with about 45% done unsafely. Abortion rates changed little between 2003 and 2008, before which they decreased for at least two decades as access to family planning and birth control increased. As of 2018, 37% of the world's women had access to legal abortions without limits as to reason. Countries that permit abortions have different limits on how late in pregnancy abortion is allowed. Abortion rates are similar between countries that ban abortion and countries that allow it.

Historically, abortions have been attempted using herbal medicines, sharp tools, forceful massage, or through other traditional methods. Abortion laws and cultural or religious views of abortions are different around the world. In some areas, abortion is legal only in specific cases such as rape, fetal defects, poverty, risk to a woman's health, or incest. There is debate over the moral, ethical, and legal issues of abortion. Those who oppose abortion often argue that an embryo or fetus is a person with a right to life, and they may compare abortion to murder. Those who support the legality of abortion often hold that it is part of a woman's right to make decisions about her own body. Others favor legal and accessible abortion as a public health measure.

Types

Induced

Approximately 205 million pregnancies occur each year worldwide. Over a third are unintended and about a fifth end in induced abortion. Most abortions result from unintended pregnancies. In the United Kingdom, 1 to 2% of abortions are done due to genetic problems in the fetus. A pregnancy can be intentionally aborted in several ways. The manner selected often depends upon the gestational age of the embryo or fetus, which increases in size as the pregnancy progresses. Specific procedures may also be selected due to legality, regional availability, and doctor or a woman's personal preference.

Reasons for procuring induced abortions are typically characterized as either therapeutic or elective. An abortion is medically referred to as a therapeutic abortion when it is performed to save the life of the pregnant woman; to prevent harm to the woman's physical or mental health; to terminate a pregnancy where indications are that the child will have a significantly increased chance of mortality or morbidity; or to selectively reduce the number of fetuses to lessen health risks associated with multiple pregnancy. An abortion is referred to as an elective or voluntary abortion when it is performed at the request of the woman for non-medical reasons. Confusion sometimes arises over the term "elective" because "elective surgery" generally refers to all scheduled surgery, whether medically necessary or not.

Spontaneous

Miscarriage, also known as spontaneous abortion, is the unintentional expulsion of an embryo or fetus before the 24th week of gestation. A pregnancy that ends before 37 weeks of gestation resulting in a live-born infant is a "premature birth" or a "preterm birth". When a fetus dies in utero after viability, 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.

Only 30% to 50% of conceptions progress past the first trimester. The vast majority of those that do not progress are lost before the woman is aware of the conception, and many pregnancies are lost before medical practitioners can detect an embryo. Between 15% and 30% of known pregnancies end in clinically apparent miscarriage, depending upon the age and health of the pregnant woman. 80% of these spontaneous abortions happen in the first trimester.

The most common cause of spontaneous abortion during the first trimester is chromosomal abnormalities of the embryo or 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 woman's 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.

Methods

Medical

 
 
Practice of Induced Abortion Methods
Induced Miscarr.
Gestational age may determine which abortion methods are practiced.

Medical abortions are those induced by abortifacient pharmaceuticals. Medical abortion became an alternative method of abortion with the availability of prostaglandin analogs in the 1970s and the antiprogestogen mifepristone (also known as RU-486) in the 1980s.

The most common early first-trimester medical abortion regimens use mifepristone in combination with misoprostol (or sometimes another prostaglandin analog, gemeprost) up to 10 weeks (70 days) gestational age, methotrexate in combination with a prostaglandin analog up to 7 weeks gestation, or a prostaglandin analog alone. Mifepristone–misoprostol combination regimens work faster and are more effective at later gestational ages than methotrexate–misoprostol combination regimens, and combination regimens are more effective than misoprostol alone. This regimen is effective in the second trimester. Medical abortion regimens involving mifepristone followed by misoprostol in the cheek between 24 and 48 hours later are effective when performed before 70 days' gestation.

In very early abortions, up to 7 weeks gestation, medical abortion using a mifepristone–misoprostol combination regimen is considered to be more effective than surgical abortion (vacuum aspiration), especially when clinical practice does not include detailed inspection of aspirated tissue. Early medical abortion regimens using mifepristone, followed 24–48 hours later by buccal or vaginal misoprostol are 98% effective up to 9 weeks gestational age; from 9 to 10 weeks efficacy decreases modestly to 94%. If medical abortion fails, surgical abortion must be used to complete the procedure.

Early medical abortions account for the majority of abortions before 9 weeks gestation in Britain, France, Switzerland, United States, and the Nordic countries.

Medical abortion regimens using mifepristone in combination with a prostaglandin analog are the most common methods used for second-trimester abortions in Canada, most of Europe, China and India, in contrast to the United States where 96% of second-trimester abortions are performed surgically by dilation and evacuation.

A 2020 Cochrane Systematic Review concluded that providing women with medications to take home to complete the second stage of the procedure for an early medical abortion results in an effective abortion. Further research is required to determine if self-administered medical abortion is as safe as provider-administered medical abortion, where a health care professional is present to help manage the medical abortion. Safely permitting women to self-administer abortion medication has the potential to improve access to abortion. Other research gaps that were identified include how to best support women who choose to take the medication home for a self-administered abortion.

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

Up to 15 weeks' gestation, suction-aspiration or vacuum aspiration are the most common surgical methods of induced abortion. Manual vacuum aspiration (MVA) consists of removing the fetus or embryo, placenta, and membranes by suction using a manual syringe, while electric vacuum aspiration (EVA) uses an electric pump. These techniques can both be used very early in pregnancy. MVA can be used up to 14 weeks but is more often used earlier in the U.S. EVA can be used later.

MVA, also known as "mini-suction" and "menstrual extraction" or EVA can be used in very early pregnancy when cervical dilation may not be required. Dilation and curettage (D&C) refers to opening the cervix (dilation) and removing tissue (curettage) via suction or sharp instruments. D&C 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. The World Health Organization recommends sharp curettage only when suction aspiration is unavailable.

Dilation and evacuation (D&E), used after 12 to 16 weeks, consists of opening the cervix and emptying the uterus using surgical instruments and suction. D&E is performed vaginally and does not require an incision. Intact dilation and extraction (D&X) refers to a variant of D&E sometimes used after 18 to 20 weeks when removal of an intact fetus improves surgical safety or for other reasons.

Abortion may also be performed surgically by hysterotomy or gravid hysterectomy. 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 can be used during later stages of pregnancy. Gravid hysterectomy refers to removal of the whole uterus while still containing the pregnancy. Hysterotomy and hysterectomy are associated with much higher rates of maternal morbidity and mortality than D&E or induction abortion.

First-trimester procedures can generally be performed using local anesthesia, while second-trimester methods may require deep sedation or general anesthesia.

Labor induction abortion

In places lacking the necessary medical skill for dilation and extraction, or where preferred by practitioners, an abortion can be induced by first inducing labor and then inducing fetal demise if necessary. This is sometimes called "induced miscarriage". This procedure may be performed from 13 weeks gestation to the third trimester. Although it is very uncommon in the United States, more than 80% of induced abortions throughout the second trimester are labor-induced abortions in Sweden and other nearby countries.

Only limited data are available comparing this method with dilation and extraction. Unlike D&E, labor-induced abortions after 18 weeks may be complicated by the occurrence of brief fetal survival, which may be legally characterized as live birth. For this reason, labor-induced abortion is legally risky in the United States.

Other methods

Historically, a number of herbs reputed to possess abortifacient properties have been used in folk medicine. Among these are: tansy, pennyroyal, black cohosh, and the now-extinct silphium.

In 1978 one woman in Colorado died and another developed organ damage when they attempted to terminate their pregnancies by taking pennyroyal oil. Because the indiscriminant use of herbs as abortifacients can cause serious—even lethal—side effects, such as multiple organ failure, such use 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. 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 and other methods to terminate pregnancy may be called "induced miscarriage". Such methods are rarely used in countries where surgical abortion is legal and available.

Safety

A likely illegal abortion flyer in South Africa

The health risks of abortion depend principally upon whether the procedure is performed safely or unsafely. The World Health Organization (WHO) defines unsafe abortions as those performed by unskilled individuals, with hazardous equipment, or in unsanitary facilities. Legal abortions performed in the developed world are among the safest procedures in medicine. In the United States as of 2012, abortion was estimated to be about 14 times safer for women than childbirth. CDC estimated in 2019 that US pregnancy-related mortality was 17.2 maternal deaths per 100,000 live births, while the US abortion mortality rate is 0.7 maternal deaths per 100,000 procedures. In the UK, guidelines of the Royal College of Obstetricians and Gynaecologists state that "Women should be advised that abortion is generally safer than continuing a pregnancy to term." Worldwide, on average, abortion is safer than carrying a pregnancy to term. A 2007 study reported that "26% of all pregnancies worldwide are terminated by induced abortion," whereas "deaths from improperly performed [abortion] procedures constitute 13% of maternal mortality globally." In Indonesia in 2000 it was estimated that 2 million pregnancies ended in abortion, 4.5 million pregnancies were carried to term, and 14-16 percent of maternal deaths resulted from abortion.

In the US from 2000 to 2009, abortion had a lower mortality rate than plastic surgery, and a similar or lower mortality rate than running a marathon. Five years after seeking abortion services, women who gave birth after being denied an abortion reported worse health than women who had either first or second trimester abortions. The risk of abortion-related mortality increases with gestational age, but remains lower than that of childbirth. Outpatient abortion is as safe from 64 to 70 days' gestation as it before 63 days.

There is little difference in terms of safety and efficacy between medical abortion using a combined regimen of mifepristone and misoprostol and surgical abortion (vacuum aspiration) in early first trimester abortions up to 10 weeks gestation. Medical abortion using the prostaglandin analog misoprostol alone is less effective and more painful than medical abortion using a combined regimen of mifepristone and misoprostol or surgical abortion.

Vacuum aspiration in the first trimester is the safest method of surgical abortion, and can be performed in a primary care office, abortion clinic, or hospital. Complications, which are rare, can include uterine perforation, pelvic infection, and retained products of conception requiring a second procedure to evacuate. Infections account for one-third of abortion-related deaths in the United States. The rate of complications of vacuum aspiration abortion in the first trimester is similar regardless of whether the procedure is performed in a hospital, surgical center, or office. Preventive antibiotics (such as doxycycline or metronidazole) are typically given before abortion procedures, as they are believed to substantially reduce the risk of postoperative uterine infection; however, antibiotics are not routinely given with abortion pills. The rate of failed procedures does not appear to vary significantly depending on whether the abortion is performed by a doctor or a mid-level practitioner.

Complications after second-trimester abortion are similar to those after first-trimester abortion, and depend somewhat on the method chosen. The risk of death from abortion approaches roughly half the risk of death from childbirth the farther along a woman is in pregnancy; from one in a million before 9 weeks gestation to nearly one in ten thousand at 21 weeks or more (as measured from the last menstrual period). It appears that having had a prior surgical uterine evacuation (whether because of induced abortion or treatment of miscarriage) correlates with a small increase in the risk of preterm birth in future pregnancies. The studies supporting this did not control for factors not related to abortion or miscarriage, and hence the causes of this correlation have not been determined, although multiple possibilities have been suggested.

Some purported risks of abortion are promoted primarily by anti-abortion groups, but lack scientific support. For example, the question of a link between induced abortion and breast cancer has been investigated extensively. Major medical and scientific bodies (including the WHO, National Cancer Institute, American Cancer Society, Royal College of OBGYN and American Congress of OBGYN) have concluded that abortion does not cause breast cancer.

In the past even illegality has not automatically meant that the abortions were unsafe. Referring to the U.S., historian Linda Gordon states: "In fact, illegal abortions in this country have an impressive safety record." According to Rickie Solinger,

A related myth, promulgated by a broad spectrum of people concerned about abortion and public policy, is that before legalization abortionists were dirty and dangerous back-alley butchers.... [T]he historical evidence does not support such claims.

Authors Jerome Bates and Edward Zawadzki describe the case of an illegal abortionist in the eastern U.S. in the early 20th century who was proud of having successfully completed 13,844 abortions without any fatality. In 1870s New York City the famous abortionist/midwife Madame Restell (Anna Trow Lohman) appears to have lost very few women among her more than 100,000 patients—a lower mortality rate than the childbirth mortality rate at the time. In 1936 the prominent professor of obstetrics and gynecology Frederick J. Taussig wrote that a cause of increasing mortality during the years of illegality in the U.S. was that

With each decade of the past fifty years the actual and proportionate frequency of this accident [perforation of the uterus] has increased, due, first, to the increase in the number of instrumentally induced abortions; second, to the proportionate increase in abortions handled by doctors as against those handled by midwives; and, third, to the prevailing tendency to use instruments instead of the finger in emptying the uterus.

Mental health

Current evidence finds no relationship between most induced abortions and mental health problems other than those expected for any unwanted pregnancy. A report by the American Psychological Association concluded that a woman's first abortion is not a threat to mental health when carried out in the first trimester, with such women no more likely to have mental-health problems than those carrying an unwanted pregnancy to term; the mental-health outcome of a woman's second or greater abortion is less certain. Some older reviews concluded that abortion was associated with an increased risk of psychological problems; however, they did not use an appropriate control group.

Although some studies show negative mental-health outcomes in women who choose abortions after the first trimester because of fetal abnormalities, more rigorous research would be needed to show this conclusively. Some proposed negative psychological effects of abortion have been referred to by anti-abortion advocates as a separate condition called "post-abortion syndrome", but this is not recognized by medical or psychological professionals in the United States.

A long term-study among US women found that about 99% of women felt that they made the right decision five years after they had an abortion. Relief was the primary emotion with few women feeling sadness or guilt. Social stigma was a main factor predicting negative emotions and regret years later.

Unsafe abortion

Soviet poster circa 1925, warning against midwives performing abortions. Title translation: "Miscarriages induced by either grandma or self-taught midwives not only maim the woman, they also often lead to death."

Women seeking an abortion may use unsafe methods, especially when it is legally restricted. They may attempt self-induced abortion or seek the help of a person without proper medical training or facilities. This can lead to severe complications, such as incomplete abortion, sepsis, hemorrhage, and damage to internal organs.

Unsafe abortions are a major cause of injury and death among women worldwide. Although data are imprecise, it is estimated that approximately 20 million unsafe abortions are performed annually, with 97% taking place in developing countries. Unsafe abortions are believed to result in millions of injuries. Estimates of deaths vary according to methodology, and have ranged from 37,000 to 70,000 in the past decade; deaths from unsafe abortion account for around 13% of all maternal deaths. The World Health Organization believes that mortality has fallen since the 1990s. To reduce the number of unsafe abortions, public health organizations have generally advocated emphasizing the legalization of abortion, training of medical personnel, and ensuring access to reproductive-health services. In response, opponents of abortion point out that abortion bans in no way affect prenatal care for women who choose to carry their fetus to term. The Dublin Declaration on Maternal Health, signed in 2012, notes, "the prohibition of abortion does not affect, in any way, the availability of optimal care to pregnant women."

A major factor in whether abortions are performed safely or not is the legal standing of abortion. Countries with restrictive abortion laws have higher rates of unsafe abortion and similar overall abortion rates compared to those where abortion is legal and available. For example, the 1996 legalization of abortion in South Africa had an immediate positive impact on the frequency of abortion-related complications, with abortion-related deaths dropping by more than 90%. Similar reductions in maternal mortality have been observed after other countries have liberalized their abortion laws, such as Romania and Nepal. A 2011 study concluded that in the United States, some state-level anti-abortion laws are correlated with lower rates of abortion in that state. The analysis, however, did not take into account travel to other states without such laws to obtain an abortion. In addition, a lack of access to effective contraception contributes to unsafe abortion. It has been estimated that the incidence of unsafe abortion could be reduced by up to 75% (from 20 million to 5 million annually) if modern family planning and maternal health services were readily available globally. Rates of such abortions may be difficult to measure because they can be reported variously as miscarriage, "induced miscarriage", "menstrual regulation", "mini-abortion", and "regulation of a delayed/suspended menstruation".

Forty percent of the world's women are able to access therapeutic and elective abortions within gestational limits, while an additional 35 percent have access to legal abortion if they meet certain physical, mental, or socioeconomic criteria. While maternal mortality seldom results from safe abortions, unsafe abortions result in 70,000 deaths and 5 million disabilities per year. Complications of unsafe abortion account for approximately an eighth of maternal mortalities worldwide, though this varies by region. Secondary infertility caused by an unsafe abortion affects an estimated 24 million women. The rate of unsafe abortions has increased from 44% to 49% between 1995 and 2008. Health education, access to family planning, and improvements in health care during and after abortion have been proposed to address this phenomenon.

Incidence

There are two commonly used methods of measuring the incidence of abortion:

  • Abortion rate – number of abortions annually per 1000 women between 15 and 44 years of age (some sources use a range of 15–49)
  • Abortion percentage – number of abortions out of 100 known pregnancies (pregnancies include live births, abortions and miscarriages)

In many places, where abortion is illegal or carries a heavy social stigma, medical reporting of abortion is not reliable. For this reason, estimates of the incidence of abortion must be made without determining certainty related to standard error.

The number of abortions performed worldwide seems to have remained stable in recent years, with 41.6 million having been performed in 2003 and 43.8 million having been performed in 2008. The abortion rate worldwide was 28 per 1000 women per year, though it was 24 per 1000 women per year for developed countries and 29 per 1000 women per year for developing countries. The same 2012 study indicated that in 2008, the estimated abortion percentage of known pregnancies was at 21% worldwide, with 26% in developed countries and 20% in developing countries.

On average, the incidence of abortion is similar in countries with restrictive abortion laws and those with more liberal access to abortion. However, restrictive abortion laws are associated with increases in the percentage of abortions performed unsafely. The unsafe abortion rate in developing countries is partly attributable to lack of access to modern contraceptives; according to the Guttmacher Institute, providing access to contraceptives would result in about 14.5 million fewer unsafe abortions and 38,000 fewer deaths from unsafe abortion annually worldwide.

The rate of legal, induced abortion varies extensively worldwide. According to the report of employees of Guttmacher Institute it ranged from 7 per 1000 women per year (Germany and Switzerland) to 30 per 1000 women per year (Estonia) in countries with complete statistics in 2008. The proportion of pregnancies that ended in induced abortion ranged from about 10% (Israel, the Netherlands and Switzerland) to 30% (Estonia) in the same group, though it might be as high as 36% in Hungary and Romania, whose statistics were deemed incomplete.

An American study in 2002 concluded that about half of women having abortions were using a form of contraception at the time of becoming pregnant. Inconsistent use was reported by half of those using condoms and three-quarters of those using the birth control 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".

The abortion rate may also be expressed as the average number of abortions a woman has during her reproductive years; this is referred to as total abortion rate (TAR).

Gestational age and method

Histogram of abortions by gestational age in England and Wales during 2019. (left) Abortion in the United States by gestational age, 2016. (right)

Abortion rates also vary depending on the stage of pregnancy and the method practiced. In 2003, the Centers for Disease Control and Prevention (CDC) reported that 26% of reported legal induced abortions in the United States were known to have been obtained at less than 6 weeks' gestation, 18% at 7 weeks, 15% at 8 weeks, 18% at 9 through 10 weeks, 10% at 11 through 12 weeks, 6% at 13 through 15 weeks, 4% at 16 through 20 weeks and 1% at more than 21 weeks. 91% of these were classified as having been done by "curettage" (suction-aspiration, dilation and curettage, dilation and evacuation), 8% by "medical" means (mifepristone), >1% by "intrauterine instillation" (saline or prostaglandin), and 1% by "other" (including hysterotomy and hysterectomy). According to the CDC, due to data collection difficulties the data must be viewed as tentative and some fetal deaths reported beyond 20 weeks may be natural deaths erroneously classified as abortions if the removal of the dead fetus is accomplished by the same procedure as an induced abortion.

The Guttmacher Institute estimated there were 2,200 intact dilation and extraction procedures in the US during 2000; this accounts for <0.2% 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 and 19 weeks, and 2% at or over 20 weeks. 64% of those reported were by vacuum aspiration, 6% by D&E, and 30% were medical. There are more second trimester abortions in developing countries such as China, India and Vietnam than in developed countries.

Motivation

Personal

A bar chart depicting selected data from a 1998 AGI meta-study on the reasons women stated for having an abortion.

The reasons why women have abortions are diverse and vary across the world. Some of the reasons may include an inability to afford a child, domestic violence, lack of support, feeling they are too young, and the wish to complete education or advance a career. Additional reasons include not being able or willing to raise a child conceived as a result of rape or incest

Societal

Some abortions are undergone as the result of societal pressures. These might include the preference for children of a specific sex or race, disapproval of single or early motherhood, stigmatization of people with disabilities, 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.

Maternal and fetal health

An additional factor is maternal health which was listed as the main reason by about a third of women in 3 of 27 countries and about 7% of women in a further 7 of these 27 countries.

In the U.S., the Supreme Court decisions in Roe v. Wade and Doe v. Bolton: "ruled that the state's interest in the life of the fetus became compelling only at the point of viability, defined as the point at which the fetus can survive independently of its mother. Even after the point of viability, the state cannot favor the life of the fetus over the life or health of the pregnant woman. Under the right of privacy, physicians must be free to use their "medical judgment for the preservation of the life or health of the mother." On the same day that the Court decided Roe, it also decided Doe v. Bolton, in which the Court defined health very broadly: "The medical judgment may be exercised in the light of all factors—physical, emotional, psychological, familial, and the woman's age—relevant to the well-being of the patient. All these factors may relate to health. This allows the attending physician the room he needs to make his best medical judgment."

Public opinion shifted in America following television personality Sherri Finkbine's discovery during her fifth month of pregnancy that she had been exposed to thalidomide. Unable to obtain a legal abortion in the United States, she traveled to Sweden. From 1962 to 1965, an outbreak of German measles left 15,000 babies with severe birth defects. In 1967, the American Medical Association publicly supported liberalization of abortion laws. A National Opinion Research Center poll in 1965 showed 73% supported abortion when the mother's life was at risk, 57% when birth defects were present and 59% for pregnancies resulting from rape or incest.

Cancer

The rate of cancer during pregnancy is 0.02–1%, and in many cases, cancer of the mother leads to consideration of abortion to protect the life of the mother, or in response to the potential damage that may occur to the fetus during treatment. This is particularly true for cervical cancer, the most common type of which occurs in 1 of every 2,000–13,000 pregnancies, for which initiation of treatment "cannot co-exist with preservation of fetal life (unless neoadjuvant chemotherapy is chosen)". Very early stage cervical cancers (I and IIa) may be treated by radical hysterectomy and pelvic lymph node dissection, radiation therapy, or both, while later stages are treated by radiotherapy. Chemotherapy may be used simultaneously. Treatment of breast cancer during pregnancy also involves fetal considerations, because lumpectomy is discouraged in favor of modified radical mastectomy unless late-term pregnancy allows follow-up radiation therapy to be administered after the birth.

Exposure to a single chemotherapy drug is estimated to cause a 7.5–17% risk of teratogenic effects on the fetus, with higher risks for multiple drug treatments. Treatment with more than 40 Gy of radiation usually causes spontaneous abortion. Exposure to much lower doses during the first trimester, especially 8 to 15 weeks of development, can cause intellectual disability or microcephaly, and exposure at this or subsequent stages can cause reduced intrauterine growth and birth weight. Exposures above 0.005–0.025 Gy cause a dose-dependent reduction in IQ. It is possible to greatly reduce exposure to radiation with abdominal shielding, depending on how far the area to be irradiated is from the fetus.

The process of birth itself may also put the mother at risk. "Vaginal delivery may result in dissemination of neoplastic cells into lymphovascular channels, haemorrhage, cervical laceration and implantation of malignant cells in the episiotomy site, while abdominal delivery may delay the initiation of non-surgical treatment."

History and religion

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.
"French Periodical Pills". An example of a clandestine advertisement published in a January 1845 edition of the Boston Daily Times.

Since ancient times abortions have been done using a number of methods, including herbal medicines, sharp tools, with force, or through other traditional methods. Induced abortion has a long history and can be traced back to civilizations as varied as ancient China (abortifacient knowledge is often attributed to the mythological ruler Shennong), ancient India since its Vedic age, ancient Egypt with its Ebers Papyrus (c. 1550 BCE), and the Roman Empire in the time of Juvenal (c. 200 CE). One of the earliest known artistic representations of abortion is in a bas relief at Angkor Wat (c. 1150). Found in a series of friezes that represent judgment after death in Hindu and Buddhist culture, it depicts the technique of abdominal abortion.

Some medical scholars and abortion opponents have suggested that the Hippocratic Oath forbade Ancient Greek physicians from performing abortions; other scholars disagree with this interpretation, and state that the medical texts of Hippocratic Corpus contain descriptions of abortive techniques right alongside the Oath. The physician Scribonius Largus wrote in 43 CE that the Hippocratic Oath prohibits abortion, as did Soranus, although apparently not all doctors adhered to it strictly at the time. According to Soranus' 1st or 2nd century CE work Gynaecology, one party of medical practitioners banished all abortives as required by the Hippocratic Oath; the other party—to which he belonged—was willing to prescribe abortions, but only for the sake of the mother's health. Aristotle, in his treatise on government Politics (350 BCE), condemns infanticide as a means of population control. He preferred abortion in such cases, with the restriction "[that it] must be practised on it before it has developed sensation and life; for the line between lawful and unlawful abortion will be marked by the fact of having sensation and being alive".

In Christianity, Pope Sixtus V (1585–90) was the first Pope before 1869 to declare that abortion is homicide regardless of the stage of pregnancy; and his pronouncement of 1588 was reversed three years later by Pope Gregory XIV. Through most of its history the Catholic Church was divided on whether it believed that early abortion was murder, and it did not begin vigorously opposing abortion until the 19th century. Several historians have written that prior to the 19th century most Catholic authors did not regard termination of pregnancy before "quickening" or "ensoulment" as an abortion. From 1750, excommunication became the punishment for abortions. Statements made in 1992 in the Catechism of the Catholic Church, the codified summary of the Church's teachings, opposed abortion.

A 2014 Guttmacher survey of US abortion patients found that many reported a religious affiliation—24% were Catholic while 30% were Protestant. A 1995 survey reported that Catholic women are as likely as the general population to terminate a pregnancy, Protestants are less likely to do so, and Evangelical Christians are the least likely to do so. Islamic tradition has traditionally permitted abortion until a point in time when Muslims believe the soul enters the fetus, considered by various theologians to be at conception, 40 days after conception, 120 days after conception, or quickening. However, abortion is largely heavily restricted or forbidden in areas of high Islamic faith such as the Middle East and North Africa.

In Europe and North America, abortion techniques advanced starting in the 17th century. However, conservatism by most physicians with regards to sexual matters prevented the wide expansion of safe abortion techniques. Other medical practitioners in addition to some physicians advertised their services, and they were not widely regulated until the 19th century, when the practice (sometimes called restellism) was banned in both the United States and the United Kingdom. Church groups as well as physicians were highly influential in anti-abortion movements. In the US, according to some sources, abortion was more dangerous than childbirth until about 1930 when incremental improvements in abortion procedures relative to childbirth made abortion safer. However, other sources maintain that in the 19th century early abortions under the hygienic conditions in which midwives usually worked were relatively safe. In addition, some commentators have written that, despite improved medical procedures, the period from the 1930s until legalization also saw more zealous enforcement of anti-abortion laws, and concomitantly an increasing control of abortion providers by organized crime.

Soviet Russia (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. Beginning in the second half of the twentieth century, abortion was legalized in a greater number of countries.

Society and culture

Abortion debate

Induced abortion has long been the source of considerable debate. Ethical, moral, philosophical, biological, religious and legal issues surrounding abortion are related to value systems. Opinions of abortion may be about fetal rights, governmental authority, and women's rights.

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. The World Medical Association Declaration on Therapeutic Abortion notes, "circumstances bringing the interests of a mother into conflict with the interests of her unborn child create a dilemma and raise the question as to whether or not the pregnancy should be deliberately terminated." Abortion debates, especially pertaining to abortion laws, are often spearheaded by groups advocating one of these two positions. Groups who favor greater legal restrictions on abortion, including complete prohibition, most often describe themselves as "pro-life" while groups who are against such legal restrictions describe themselves as "pro-choice". Generally, the former position argues that a human fetus is a human person with a right to live, making abortion morally the same as murder. The latter position argues that a woman has certain reproductive rights, especially the right to decide whether or not to carry a pregnancy to term.

Modern abortion law


Legal grounds for abortion by country
  Legal on woman's request
Legally restricted to cases of:
  Risk to woman's life, her health*, rape*, fetal impairment*, or socioeconomic factors
  Risk to woman's life, her health*, rape, or fetal impairment
  Risk to woman's life, her health*, or fetal impairment
  Risk to woman's life*, her health*, or rape
  Risk to woman's life or her health
  Risk to woman's life
  Illegal with no exceptions
  No information
* Does not apply to some countries in that category

Current laws pertaining to abortion are diverse. Religious, moral, and cultural factors 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 sometimes constitute the basis for the existence or absence of abortion laws.

In jurisdictions where abortion is legal, certain requirements must often be met before a woman may obtain a safe, legal abortion (an abortion performed without the woman's consent is considered feticide). These requirements usually depend on the age of the fetus, often using a trimester-based system to regulate the window of legality, or as in the U.S., on a doctor's evaluation of the fetus' viability. Some jurisdictions require a 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. Other jurisdictions may require that a woman obtain the consent of the fetus' father before aborting the fetus, that abortion providers inform women of health risks of the procedure—sometimes including "risks" not supported by the medical literature—and that multiple medical authorities certify that the abortion is either medically or socially necessary. Many restrictions are waived in emergency situations. China, which has ended their one-child policy, and now has a two child policy, has at times incorporated mandatory abortions as part of their population control strategy.

Other jurisdictions ban abortion almost entirely. Many, but not all, of these allow legal abortions in a variety of circumstances. These circumstances vary based on jurisdiction, but may include whether the pregnancy is a result of rape or incest, the fetus' development is impaired, the woman's physical or mental well-being is endangered, or socioeconomic considerations make childbirth a hardship. In countries where abortion is banned entirely, such as Nicaragua, medical authorities have recorded rises in maternal death directly and indirectly due to pregnancy as well as deaths due to doctors' fears of prosecution if they treat other gynecological emergencies. Some countries, such as Bangladesh, that nominally ban abortion, may also support clinics that perform abortions under the guise of menstrual hygiene. This is also a terminology in traditional medicine. 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 attempt to perform an abortion by themselves.

The organization Women on Waves has been providing education about medical abortions since 1999. The NGO created a mobile medical clinic inside a shipping container, which then travels on rented ships to countries with restrictive abortion laws. Because the ships are registered in the Netherlands, Dutch law prevails when the ship is in international waters. While in port, the organization provides free workshops and education; while in international waters, medical personnel are legally able to prescribe medical abortion drugs and counseling.

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 termination of a fetus based on its sex. The selective termination of a female fetus is most common.

Sex-selective abortion is partially responsible for the noticeable disparities between the birth rates of male and female children in some countries. The preference for male children is reported in many areas of Asia, and abortion used to limit female births has been reported in Taiwan, South Korea, India, and China. This deviation from the standard birth rates of males and females occurs despite the fact that the country in question may have officially banned sex-selective abortion or even sex-screening. In China, a historical preference for a male child has been exacerbated by the one-child policy, which was enacted in 1979.

Many countries have taken legislative steps to reduce the incidence of sex-selective abortion. At the International Conference on Population and Development in 1994 over 180 states agreed to eliminate "all forms of discrimination against the girl child and the root causes of son preference", conditions also condemned by a PACE resolution in 2011. The World Health Organization and UNICEF, along with other United Nations agencies, have found that measures to reduce access to abortion are much less effective at reducing sex-selective abortions than measures to reduce gender inequality.

Anti-abortion violence

In a number of cases, abortion providers and these facilities have been subjected to various forms of violence, including murder, attempted murder, kidnapping, stalking, assault, arson, and bombing. Anti-abortion violence is classified by both governmental and scholarly sources as terrorism. In the U.S. and Canada, over 8,000 incidents of violence, trespassing, and death threats have been recorded by providers since 1977, including over 200 bombings/arsons and hundreds of assaults. The majority of abortion opponents have not been involved in violent acts.

In the United States, four physicians who performed abortions have been murdered: David Gunn (1993), John Britton (1994), Barnett Slepian (1998), and George Tiller (2009). Also murdered, in the U.S. and Australia, have been other personnel at abortion clinics, including receptionists and security guards such as James Barrett, Shannon Lowney, Lee Ann Nichols, and Robert Sanderson. Woundings (e.g., Garson Romalis) and attempted murders have also taken place in the United States and Canada. Hundreds of bombings, arsons, acid attacks, invasions, and incidents of vandalism against abortion providers have occurred. Notable perpetrators of anti-abortion violence include Eric Robert Rudolph, Scott Roeder, Shelley Shannon, and Paul Jennings Hill, the first person to be executed in the United States for murdering an abortion provider.

Legal protection of access to abortion has been brought into some countries where abortion is legal. These laws typically seek to protect abortion clinics from obstruction, vandalism, picketing, and other actions, or to protect women and employees of such facilities from threats and harassment.

Far more common than physical violence is psychological pressure. In 2003, Chris Danze organized anti-abortion organizations throughout Texas to prevent the construction of a Planned Parenthood facility in Austin. The organizations released the personal information online, of those involved with construction, sending them up to 1200 phone calls a day and contacting their churches. Some protestors record women entering clinics on camera.

Other animals

Spontaneous abortion occurs in various animals. For example, in sheep it may be caused by stress or physical exertion, such as 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. Eating pine needles can also induce abortions in cows. Several plants, including broomweed, skunk cabbage, poison hemlock, and tree tobacco, are known to cause fetal deformities and abortion in cattle and in sheep and goats. In horses, a fetus may be aborted or resorbed if it has lethal white syndrome (congenital intestinal aganglionosis). Foal embryos that are homozygous for the dominant white gene (WW) are theorized to also be aborted or resorbed before birth. In many species of sharks and rays, stress-induced abortions occur frequently on capture.

Viral infection can cause abortion in dogs. Cats can experience spontaneous abortion for many reasons, including hormonal imbalance. A combined abortion and spaying is performed on pregnant cats, especially in trap–neuter–return programs, to prevent unwanted kittens from being born. Female rodents may terminate a pregnancy when exposed to the smell of a male not responsible for the pregnancy, known as the Bruce effect.

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.

Monday, September 20, 2021

Stem cell controversy

From Wikipedia, the free encyclopedia

The stem cell controversy is the consideration of the ethics of research involving the development and use of human embryos. Most commonly, this controversy focuses on embryonic stem cells. Not all stem cell research involves human embryos. For example, adult stem cells, amniotic stem cells, and induced pluripotent stem cells do not involve creating, using, or destroying human embryos, and thus are minimally, if at all, controversial. Many less controversial sources of acquiring stem cells include using cells from the umbilical cord, breast milk, and bone marrow, which are not pluripotent.

Background

For many decades, stem cells have played an important role in medical research, beginning in 1868 when Ernst Haeckel first used the phrase to describe the fertilized egg which eventually gestates into an organism. The term was later used in 1886 by William Sedgwick to describe the parts of a plant that grow and regenerate. Further work by Alexander Maximow and Leroy Stevens introduced the concept that stem cells are pluripotent. This significant discovery led to the first human bone marrow transplant by E. Donnal Thomas in 1956, which although successful in saving lives, has generated much controversy since. This has included the many complications inherent in stem cell transplantation (almost 200 allogeneic marrow transplants were performed in humans, with no long-term successes before the first successful treatment was made), through to more modern problems, such as how many cells are sufficient for engraftment of various types of hematopoietic stem cell transplants, whether older patients should undergo transplant therapy, and the role of irradiation-based therapies in preparation for transplantation.

The discovery of adult stem cells led scientists to develop an interest in the role of embryonic stem cells, and in separate studies in 1981 Gail Martin and Martin Evans derived pluripotent stem cells from the embryos of mice for the first time. This paved the way for Mario Capecchi, Martin Evans, and Oliver Smithies to create the first knockout mouse, ushering in a whole new era of research on human disease. In 1995 adult stem cell research with human use was patented (US PTO with effect from 1995). In fact, human use was published in World J Surg 1991 & 1999 (B G Matapurkar). Salhan, Sudha (August 2011).

In 1998, James Thomson and Jeffrey Jones derived the first human embryonic stem cells, with even greater potential for drug discovery and therapeutic transplantation. However, the use of the technique on human embryos led to more widespread controversy as criticism of the technique now began from the wider public who debated the moral ethics of questions concerning research involving human embryonic cells.

Potential use in therapy

Since pluripotent stem cells have the ability to differentiate into any type of cell, they are used in the development of medical treatments for a wide range of conditions. Treatments that have been proposed include treatment for physical trauma, degenerative conditions, and genetic diseases (in combination with gene therapy). Yet further treatments using stem cells could potentially be developed due to their ability to repair extensive tissue damage.

Great levels of success and potential have been realized from research using adult stem cells. In early 2009, the FDA approved the first human clinical trials using embryonic stem cells. Only cells from an embryo at the morula stage or earlier are truly totipotent, meaning that they are able to form all cell types including placental cells. Adult stem cells are generally limited to differentiating into different cell types of their tissue of origin. However, some evidence suggests that adult stem cell plasticity may exist, increasing the number of cell types a given adult stem cell can become.

Points of controversy

Many of the debates surrounding human embryonic stem cells concern issues such as what things and research should be made on studies using these types of cells. At what point does one consider life to begin? Is it just to destroy a human embryo if it has the potential to cure countless numbers of patients? Political leaders debate how to regulate and fund research studies that involve the techniques used to remove the embryo cells. No clear consensus has emerged. Other recent discoveries may extinguish the need for embryonic stem cells.

Much of the criticism has been a result of religious beliefs and, in the most high-profile case, US President George W Bush signed an executive order banning the use of federal funding for any cell lines other than those already in existence, stating at the time, "My position on these issues is shaped by deeply held beliefs," and "I also believe human life is a sacred gift from our creator." This ban was in part revoked by his successor Barack Obama, who stated : "As a person of faith, I believe we are called to care for each other and work to ease human suffering. I believe we have been given the capacity and will to pursue this research and the humanity and conscience to do so responsibly."

Potential solutions

Some stem cell researchers are working to develop techniques of isolating stem cells that are as potent as embryonic stem cells, but do not require a human embryo.

Foremost among these was the discovery in August 2006 that adult cells can be reprogrammed into a pluripotent state by the introduction of four specific transcription factors, resulting in induced pluripotent stem cells. This major breakthrough won a Nobel Prize for the discoverers, Shinya Yamanaka and John Gurdon.

In an alternative technique, researchers at Harvard University, led by Kevin Eggan and Savitri Marajh, have transferred the nucleus of a somatic cell into an existing embryonic stem cell, thus creating a new stem cell line.

Researchers at Advanced Cell Technology, led by Robert Lanza and Travis Wahl, reported the successful derivation of a stem cell line using a process similar to preimplantation genetic diagnosis, in which a single blastomere is extracted from a blastocyst. At the 2007 meeting of the International Society for Stem Cell Research (ISSCR), Lanza announced that his team had succeeded in producing three new stem cell lines without destroying the parent embryos. "These are the first human embryonic cell lines in existence that didn't result from the destruction of an embryo." Lanza is currently in discussions with the National Institutes of Health to determine whether the new technique sidesteps U.S. restrictions on federal funding for ES cell research.

Anthony Atala of Wake Forest University says that the fluid surrounding the fetus has been found to contain stem cells that, when used correctly, "can be differentiated towards cell types such as fat, bone, muscle, blood vessel, nerve and liver cells." The extraction of this fluid is not thought to harm the fetus in any way. He hopes "that these cells will provide a valuable resource for tissue repair and for engineered organs, as well."

Viewpoints

Stem cell debates have motivated and reinvigorated the anti-abortion movement, whose members are concerned with the rights and status of the human embryo as an early-aged human life. They believe that embryonic stem cell research profits from and violates the sanctity of life and is tantamount to murder. The fundamental assertion of those who oppose embryonic stem cell research is the belief that human life is inviolable, combined with the belief that human life begins when a sperm cell fertilizes an egg cell to form a single cell. The view of those in favor is that these embryos would otherwise be discarded, and if used as stem cells, they can survive as a part of a living human person.

A portion of stem cell researchers use embryos that were created but not used in in vitro fertility treatments to derive new stem cell lines. Most of these embryos are to be destroyed, or stored for long periods of time, long past their viable storage life. In the United States alone, an estimated at least 400,000 such embryos exist. This has led some opponents of abortion, such as Senator Orrin Hatch, to support human embryonic stem cell research.

Medical researchers widely report that stem cell research has the potential to dramatically alter approaches to understanding and treating diseases, and to alleviate suffering. In the future, most medical researchers anticipate being able to use technologies derived from stem cell research to treat a variety of diseases and impairments. Spinal cord injuries and Parkinson's disease are two examples that have been championed by high-profile media personalities (for instance, Christopher Reeve and Michael J. Fox, who have lived with these conditions, respectively). The anticipated medical benefits of stem cell research add urgency to the debates, which has been appealed to by proponents of embryonic stem cell research.

In August 2000, The U.S. National Institutes of Health's Guidelines stated:

... research involving human pluripotent stem cells ... promises new treatments and possible cures for many debilitating diseases and injuries, including Parkinson's disease, diabetes, heart disease, multiple sclerosis, burns and spinal cord injuries. The NIH believes the potential medical benefits of human pluripotent stem cell technology are compelling and worthy of pursuit in accordance with appropriate ethical standards.

In 2006, researchers at Advanced Cell Technology of Worcester, Massachusetts, succeeded in obtaining stem cells from mouse embryos without destroying the embryos. If this technique and its reliability are improved, it would alleviate some of the ethical concerns related to embryonic stem cell research.

Another technique announced in 2007 may also defuse the longstanding debate and controversy. Research teams in the United States and Japan have developed a simple and cost-effective method of reprogramming human skin cells to function much like embryonic stem cells by introducing artificial viruses. While extracting and cloning stem cells is complex and extremely expensive, the newly discovered method of reprogramming cells is much cheaper. However, the technique may disrupt the DNA in the new stem cells, resulting in damaged and cancerous tissue. More research will be required before noncancerous stem cells can be created.

Update of article to include 2009/2010 current stem cell usages in clinical trials: The planned treatment trials will focus on the effects of oral lithium on neurological function in people with chronic spinal cord injury and those who have received umbilical cord blood mononuclear cell transplants to the spinal cord. The interest in these two treatments derives from recent reports indicating that umbilical cord blood stem cells may be beneficial for spinal cord injury and that lithium may promote regeneration and recovery of function after spinal cord injury. Both lithium and umbilical cord blood are widely available therapies that have long been used to treat diseases in humans.

Endorsement

  • Embryonic stem cells have the potential to grow indefinitely in a laboratory environment and can differentiate into almost all types of bodily tissue. This makes embryonic stem cells a prospect for cellular therapies to treat a wide range of diseases.

Human potential and humanity

This argument often goes hand-in-hand with the utilitarian argument, and can be presented in several forms:

  • Embryos are not equivalent to human life while they are still incapable of surviving outside the womb (i.e. they only have the potential for life).
  • More than a third of zygotes do not implant after conception. Thus, far more embryos are lost due to chance than are proposed to be used for embryonic stem cell research or treatments.
  • Blastocysts are a cluster of human cells that have not differentiated into distinct organ tissue, making cells of the inner cell mass no more "human" than a skin cell.
  • Some parties contend that embryos are not human persons, believing that the life of Homo sapiens only begins when the heartbeat develops, which is during the fifth week of pregnancy, or when the brain begins developing activity, which has been detected at 54 days after conception.

Efficiency

  • In vitro fertilization (IVF) generates large numbers of unused embryos (e.g. 70,000 in Australia alone). Many of these thousands of IVF embryos are slated for destruction. Using them for scientific research uses a resource that would otherwise be wasted.
  • While the destruction of human embryos is required to establish a stem cell line, no new embryos have to be destroyed to work with existing stem cell lines. It would be wasteful not to continue to make use of these cell lines as a resource.

Superiority

This is usually presented as a counter-argument to using adult stem cells, as an alternative that does not involve embryonic destruction.

  • Embryonic stem cells make up a significant proportion of a developing embryo, while adult stem cells exist as minor populations within a mature individual (e.g. in every 1,000 cells of the bone marrow, only one will be a usable stem cell). Thus, embryonic stem cells are likely to be easier to isolate and grow ex vivo than adult stem cells.
  • Embryonic stem cells divide more rapidly than adult stem cells, potentially making it easier to generate large numbers of cells for therapeutic means. In contrast, adult stem cell might not divide fast enough to offer immediate treatment.
  • Embryonic stem cells have greater plasticity, potentially allowing them to treat a wider range of diseases.
  • Adult stem cells from the patient's own body might not be effective in treatment of genetic disorders. Allogeneic embryonic stem cell transplantation (i.e. from a healthy donor) may be more practical in these cases than gene therapy of a patient's own cell.
  • DNA abnormalities found in adult stem cells that are caused by toxins and sunlight may make them poorly suited for treatment.
  • Embryonic stem cells have been shown to be effective in treating heart damage in mice.
  • Embryonic stem cells have the potential to cure chronic and degenerative diseases which current medicine has been unable to effectively treat.

Individuality

  • Before the primitive streak is formed when the embryo attaches to the uterus around 14 days after fertilization, two fertilized eggs can combine by fusing together and develop into one person (a tetragametic chimera). Since a fertilized egg has the potential to be two individuals or half of one, some believe it can only be considered a 'potential' person, not an actual one. Those who subscribe to this belief then hold that destroying a blastocyst for embryonic stem cells is ethical.

Viability

  • Viability is another standard under which embryos and fetuses have been regarded as human lives. In the United States, the 1973 Supreme Court case of Roe v. Wade concluded that viability determined the permissibility of abortions performed for reasons other than the protection of the woman's health, defining viability as the point at which a fetus is "potentially able to live outside the mother's womb, albeit with artificial aid." The point of viability was 24 to 28 weeks when the case was decided and has since moved to about 22 weeks due to advancement in medical technology. Embryos used in medical research for stem cells are well below development that would enable viability.

Objection

Alternatives

This argument is used by opponents of embryonic destruction, as well as researchers specializing in adult stem cell research.

Pro-life supporters often claim that the use of adult stem cells from sources such as the umbilical cord blood has consistently produced more promising results than the use of embryonic stem cells. Furthermore, adult stem cell research may be able to make greater advances if less money and resources were channeled into embryonic stem cell research. Stem cell research is highly frowned upon in many ethnic and religious groups.

In the past, it has been a necessity to research embryonic stem cells and in doing so destroy them for research to progress. As a result of the research done with both embryonic and adult stem cells, new techniques may make the necessity for embryonic cell research obsolete. Because many of the restrictions placed on stem cell research have been based on moral dilemmas surrounding the use of embryonic cells, there will likely be rapid advancement in the field as the techniques that created those issues are becoming less of a necessity. Many funding and research restrictions on embryonic cell research will not impact research on IPSCs (induced pluripotent stem cells) allowing for a promising portion of the field of research to continue relatively unhindered by the ethical issues of embryonic research.

Adult stem cells have provided many different therapies for illnesses such as Parkinson's disease, leukemia, multiple sclerosis, lupus, sickle-cell anemia, and heart damage (to date, embryonic stem cells have also been used in treatment), Moreover, there have been many advances in adult stem cell research, including a recent study where pluripotent adult stem cells were manufactured from differentiated fibroblast by the addition of specific transcription factors. Newly created stem cells were developed into an embryo and were integrated into newborn mouse tissues, analogous to the properties of embryonic stem cells.

Stated views of groups

Government policy stances

Europe

Austria, Denmark, France, Germany, Portugal and Ireland do not allow the production of embryonic stem cell lines, but the creation of embryonic stem cell lines is permitted in Finland, Greece, the Netherlands, Sweden, and the United Kingdom.

United States

Origins

In 1973, Roe v. Wade legalized abortion in the United States. Five years later, the first successful human in vitro fertilization resulted in the birth of Louise Brown in England. These developments prompted the federal government to create regulations barring the use of federal funds for research that experimented on human embryos. In 1995, the NIH Human Embryo Research Panel advised the administration of President Bill Clinton to permit federal funding for research on embryos left over from in vitro fertility treatments and also recommended federal funding of research on embryos specifically created for experimentation. In response to the panel's recommendations, the Clinton administration, citing moral and ethical concerns, declined to fund research on embryos created solely for research purposes, but did agree to fund research on leftover embryos created by in vitro fertility treatments. At this point, the Congress intervened and passed the 1995 Dickey–Wicker Amendment (the final bill, which included the Dickey-Wicker Amendment, was signed into law by Bill Clinton) which prohibited any federal funding for the Department of Health and Human Services be used for research that resulted in the destruction of an embryo regardless of the source of that embryo.

In 1998, privately funded research led to the breakthrough discovery of human embryonic stem cells (hESC). This prompted the Clinton administration to re-examine guidelines for federal funding of embryonic research. In 1999, the president's National Bioethics Advisory Commission recommended that hESC harvested from embryos discarded after in vitro fertility treatments, but not from embryos created expressly for experimentation, be eligible for federal funding. Though embryo destruction had been inevitable in the process of harvesting hESC in the past (this is no longer the case), the Clinton administration had decided that it would be permissible under the Dickey-Wicker Amendment to fund hESC research as long as such research did not itself directly cause the destruction of an embryo. Therefore, HHS issued its proposed regulation concerning hESC funding in 2001. Enactment of the new guidelines was delayed by the incoming George W. Bush administration which decided to reconsider the issue.

President Bush announced, on August 9, 2001, that federal funds, for the first time, would be made available for hESC research on currently existing embryonic stem cell lines. President Bush authorized research on existing human embryonic stem cell lines, not on human embryos under a specific, unrealistic timeline in which the stem cell lines must have been developed. However, the Bush Administration chose not to permit taxpayer funding for research on hESC cell lines not currently in existence, thus limiting federal funding to research in which "the life-and-death decision has already been made." The Bush Administration's guidelines differ from the Clinton Administration guidelines which did not distinguish between currently existing and not-yet-existing hESC. Both the Bush and Clinton guidelines agree that the federal government should not fund hESC research that directly destroys embryos.

Neither Congress nor any administration has ever prohibited private funding of embryonic research. Public and private funding of research on adult and cord blood stem cells is unrestricted.

U.S. Congressional response

In April 2004, 206 members of Congress signed a letter urging President Bush to expand federal funding of embryonic stem cell research beyond what Bush had already supported.

In May 2005, the House of Representatives voted 238–194 to loosen the limitations on federally funded embryonic stem-cell research – by allowing government-funded research on surplus frozen embryos from in vitro fertilization clinics to be used for stem cell research with the permission of donors – despite Bush's promise to veto the bill if passed. On July 29, 2005, Senate Majority Leader William H. Frist (R-TN) announced that he too favored loosening restrictions on federal funding of embryonic stem cell research. On July 18, 2006, the Senate passed three different bills concerning stem cell research. The Senate passed the first bill (the Stem Cell Research Enhancement Act) 63–37, which would have made it legal for the federal government to spend federal money on embryonic stem cell research that uses embryos left over from in vitro fertilization procedures. On July 19, 2006, President Bush vetoed this bill. The second bill makes it illegal to create, grow, and abort fetuses for research purposes. The third bill would encourage research that would isolate pluripotent, i.e., embryonic-like, stem cells without the destruction of human embryos.

In 2005 and 2007, Congressman Ron Paul introduced the Cures Can Be Found Act, with 10 cosponsors. With an income tax credit, the bill favors research upon non-embryonic stem cells obtained from placentas, umbilical cord blood, amniotic fluid, humans after birth, or unborn human offspring who died of natural causes; the bill was referred to committee. Paul argued that hESC research is outside of federal jurisdiction either to ban or to subsidize.

Bush vetoed another bill, the Stem Cell Research Enhancement Act of 2007, which would have amended the Public Health Service Act to provide for human embryonic stem cell research. The bill passed the Senate on April 11 by a vote of 63–34, then passed the House on June 7 by a vote of 247–176. President Bush vetoed the bill on July 19, 2007.

On March 9, 2009, President Obama removed the restriction on federal funding for newer stem cell lines. Two days after Obama removed the restriction, the president then signed the Omnibus Appropriations Act of 2009, which still contained the long-standing Dickey–Wicker Amendment which bans federal funding of "research in which a human embryo or embryos are destroyed, discarded, or knowingly subjected to risk of injury or death;" the Congressional provision effectively prevents federal funding being used to create new stem cell lines by many of the known methods. So, while scientists might not be free to create new lines with federal funding, President Obama's policy allows the potential of applying for such funding into research involving the hundreds of existing stem cell lines as well as any further lines created using private funds or state-level funding. The ability to apply for federal funding for stem cell lines created in the private sector is a significant expansion of options over the limits imposed by President Bush, who restricted funding to the 21 viable stem cell lines that were created before he announced his decision in 2001. The ethical concerns raised during Clinton's time in office continue to restrict hESC research and dozens of stem cell lines have been excluded from funding, now by judgment of an administrative office rather than presidential or legislative discretion.

Funding

In 2005, the NIH funded $607 million worth of stem cell research, of which $39 million was specifically used for hESC. Sigrid Fry-Revere has argued that private organizations, not the federal government, should provide funding for stem-cell research, so that shifts in public opinion and government policy would not bring valuable scientific research to a grinding halt.

In 2005, the State of California took out $3 billion in bond loans to fund embryonic stem cell research in that state.

Asia

China has one of the most permissive human embryonic stem cell policies in the world. In the absence of a public controversy, human embryo stem cell research is supported by policies that allow the use of human embryos and therapeutic cloning.

Religious views

Generally speaking, no group advocates for unrestricted stem cell research, especially in the context of embryonic stem cell research.

Jewish view

According to Rabbi Levi Yitzchak Halperin of the Institute for Science and Jewish Law in Jerusalem, embryonic stem cell research is permitted so long as it has not been implanted in the womb. Not only is it permitted, but research is encouraged, rather than wasting it.

As long as it has not been implanted in the womb and it is still a frozen fertilized egg, it does not have the status of an embryo at all and there is no prohibition to destroy it...

However in order to remove all doubt [as to the permissibility of destroying it], it is preferable not to destroy the pre-embryo unless it will otherwise not be implanted in the woman who gave the eggs (either because there are many fertilized eggs, or because one of the parties refuses to go on with the procedure – the husband or wife – or for any other reason). Certainly it should not be implanted into another woman.... The best and worthiest solution is to use it for life-saving purposes, such as for the treatment of people that suffered trauma to their nervous system, etc.

— Rabbi Levi Yitzchak Halperin, Ma'aseh Choshev vol. 3, 2:6

Similarly, the sole Jewish majority state, Israel, permits research on embryonic stem cells.

Catholicism

The Catholic Church opposes human embryonic stem cell research calling it "an absolutely unacceptable act." The Church supports research that involves stem cells from adult tissues and the umbilical cord, as it "involves no harm to human beings at any state of development." This support has been expressed both politically and financially, with different Catholic groups either raising money indirectly, offering grants, or seeking to pass federal legislation, according to the United States Conference of Catholic Bishops. Specific examples include a grant from the Catholic Archiocese of Sydney which funded research demonstrating the capabilities of adult stem cells, and the U.S. Conference of Catholic Bishops working to pass federal legislation creating a nationwide public bank for umbilical cord blood stem cells.

Baptists

The Southern Baptist Convention opposes human embryonic stem cell research on the grounds that the "Bible teaches that human beings are made in the image and likeness of God (Gen. 1:27; 9:6) and protectable human life begins at fertilization." However, it supports adult stem cell research as it does "not require the destruction of embryos."

Methodism

The United Methodist Church opposes human embryonic stem cell research, saying, "a human embryo, even at its earliest stages, commands our reverence." However, it supports adult stem cell research, stating that there are "few moral questions" raised by this issue.

Pentecostalism

The Assemblies of God opposes human embryonic stem cell research, saying, it "perpetuates the evil of abortion and should be prohibited."

Islam

Islamic scholars generally favor the stance that scientific research and development of stem cells is allowed as long as it benefits society while causing the least amount of harm to the subjects. "Stem cell research is one of the most controversial topics of our time period and has raised many religious and ethical questions regarding the research being done. With there being no true guidelines set forth in the Qur'an against the study of biomedical testing, Muslims have adopted any new studies as long as the studies do not contradict another teaching in the Qur'an. One of the teachings of the Qur'an states that 'Whosoever saves the life of one, it shall be if he saves the life of humankind' (5:32), it is this teaching that makes stem cell research acceptable in the Muslim faith because of its promise of potential medical breakthrough." This statement does not, however, make a distinction between adult, embryonic, or stem-cells. In specific instances, different sources have issued fatwas, or nonbinding but authoritative legal opinions according to Islamic faith, ruling on conduct in stem cell research. The Fatwa of the Islamic Jurisprudence Council of the Islamic World League (December 2003) addressed permissible stem cell sources, as did the Fatwa Khomenei (2002) in Iran. Several different governments in predominantly Muslim countries have also supported stem cell research, notably Saudi Arabia and Iran.

The Church of Jesus Christ of Latter-day Saints

The First Presidency of The Church of Jesus Christ of Latter-day Saints "has not taken a position regarding the use of embryonic stem cells for research purposes. The absence of a position should not be interpreted as support for or opposition to any other statement made by Church members, whether they are for or against embryonic stem cell research.”

 

Equality (mathematics)

From Wikipedia, the free encyclopedia https://en.wikipedia.org/wiki/Equality_...