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Forms of EC include:
Forms of EC include:
* Emergency contraceptive pill &mdash;referred to simply as "emergency contraception," "ECPs," or "ECs", or "morning-after pill" &mdash;are hormones that act both to prevent [[ovulation]] or [[fertilisation]], or possibly, post-fertilisation, subsequent [[Pregnancy|implantation]] of a [[blastocyst]] ([[embryo]]).<ref>A minority view within the medical community, along with many [[pro-life]] advocates, argue for a [[Beginning of pregnancy controversy|different definition of pregnancy]], see [[Emergency contraception#Controversy in relation to abortion|Controversy section]] for more detail.</ref>
* Emergency contraceptive pill &mdash;referred to simply as "emergency contraception," "ECPs," or "ECs", or "morning-after pill" &mdash;are hormones that act both to prevent [[ovulation]] or [[fertilisation]], or possibly, post-fertilisation, subsequent [[Pregnancy|implantation]] of a [[blastocyst]] ([[embryo]]). ECPs are not to be confused with [[chemical abortion]] methods that act after implantation has occurred.<ref>A minority view within the medical community, along with many [[pro-life]] advocates, argue for a [[Beginning of pregnancy controversy|different definition of pregnancy]], see [[Emergency contraception#Controversy in relation to abortion|Controversy section]] for more detail.</ref>
* [[Intrauterine device]]s (IUDs) - usually used as a primary contraception method, but sometimes used as emergency contraception.
* [[Intrauterine device]]s (IUDs) - usually used as a primary contraception method, but sometimes used as emergency contraception.


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=== U.S. Legal Controversies ===
=== U.S. Legal Controversies ===


A [[Massachusetts]] law that went into effect on [[14 December]], 2005, requires all [[hospital]]s in the state to provide emergency contraception to any "female rape victim of childbearing age" <ref>Commonwealth of Massachusetts Chapter 91 of the Acts of 2005. "[http://www.mass.gov/legis/laws/seslaw05/sl050091.htm An Act Providing Timely Access to Emergency Contraception.]" Enacted September 15, 2005. Accessed April 28, 2006.</ref> including Catholic Hospitals who oppose the provision of emergency contraception. In a letter criticizing the joint [[United Nations|UN]]/[[World Health Organization|WHO]] ''Inter-agency Field Manual on Reproductive Health in Refugee Situations'', the Catholic Church explains its belief that emergency contraception, along with [[Intrauterine Device|IUDs]] and [[Progestagen|hormonal]] [[Birth control|contraception]], cannot be considered "solely contraceptive because in the case of effective fertilisation a chemical abortion would be carried out during the first days of pregnancy."<ref>Barragán, Javier L., Hamao, Stephen F., and Trujillo, Alfonsocard L. [http://www.vatican.va/roman_curia/pontifical_councils/migrants/documents/rc_pc_migrants_doc_2003072_salud%20reproductiva_en.html The Reproductive Health of Refugees]. Pontifical Council for the Pastoral Care of Migrants and Itinerant People. September 14, 2001. Accessed April 28, 2006.</ref> The Catholic position on family planning is explained further in ''Ethical and Religious Directives for Catholic Health Care Services.''<ref>"[http://www.usccb.org/bishops/directives.shtml Ethical and Religious Directives for Catholic Health Care Services, Fourth Edition]." ''United States Conference of Catholic Bishops.'' 2001. Accessed April 28, 2006.</ref> Because of this expressed moral stance against emergency contraception, the Massachusetts Catholic Conference opposed this law, stating interference with [[Freedom of religion|religious freedom]].
A [[Massachusetts]] law that went into effect on [[14 December]], 2005, requires all [[hospital]]s in the state to provide emergency contraception to any "female rape victim of childbearing age" <ref>Commonwealth of Massachusetts Chapter 91 of the Acts of 2005. "[http://www.mass.gov/legis/laws/seslaw05/sl050091.h

==Related statistics and studies==
*More than 300,000 women are sexually assaulted each year in the US.<ref>{{cite journal | last = Tjaden | first = Patricia | coauthors = Nancy Thoennes | year = 2006 | month = January | title = Extent, Nature, and Consequences of Rape Victimization: Findings From the National Violence Against Women Survey | publisher = [[National Institute of Justice]] | url = http://www.ncjrs.gov/pdffiles1/nij/210346.pdf | accessdate = 2006-08-23}}</ref> An estimated 25,000 of these sexual assaults will result in pregnancy. About 22,000 of these pregnancies could be prevented if all women who were raped had easy access to emergency contraception.<ref>{{cite journal | last = Stewart | first = Felicia H. | coauthors = James Trussell. | year = 2000 | month = November | title = Prevention of pregnancy resulting from rape: A neglected preventive health measure | journal = American Journal of Preventive Medicine | volume = 19 | issue = 4 | page = 228-229 | id = PMID 11064225| doi = 10.1016/S0749-3797(00)00243-9| url = http://www.ingentaconnect.com/content/els/07493797/2000/00000019/00000004/art00243;jsessionid=12ho4w9a3akpe.alice | accessdate = 2006-08-23}}</ref>
*A [[Guttmacher Institute]] journal reported that:
**Abortions because of rape account for less than one percent of all annual abortions. <ref>{{cite journal | last = Finer | first = Lawrence B. | coauthors = Lori F. Frohwirth, Lindsay A. Dauphinee, Susheela Singh, and Ann M. Moore | year = 2005 | month = September | title = Reasons U.S. Women Have Abortions: Quantitative and Qualitative Perspectives | journal = Perspectives on Sexual and Reproductive Health | volume = 37 | issue = 3 | pages = 110-118 | url = http://www.guttmacher.org/pubs/journals/3711005.pdf | id = PMID 16150658 | accessdate = 2006-08-23}}</ref>
**nearly one half of America's 6.4 million annual pregnancies are accidental<ref name="posarh382">{{cite journal | last = Finer | first = Lawrence B. | coauthors = Stanley K. Henshaw | year = 2006 | month = June | title = Disparities in Rates of Unintended Pregnancy in the United States, 1994 and 2001 | journal = Perspectives on Sexual and Reproductive Health | volume = 38 | issue = 2 | url = http://www.guttmacher.org/pubs/journals/3809006.html | id = PMID 16772190 | accessdate = 2006-08-23}}</ref>
**unintended pregnancies result in 1.3 million abortions annually<ref name="posarh382" />
*A study in the UK reported that "the shift towards greater promotion of emergency birth control appears to have (...) worsened the impact of STI rates since 2000."<ref>Paton, David. [http://www.swan.ac.uk/economics/res2004/program/papers/Paton.pdf "Random Behavior or Rational Choice? Family Planning, Teenage Pregnancy, and STIs]. (2003).</ref> It should be noted that the business professor who wrote this paper has yet to publish this paper in a peer reviewed journal. Peer review is a fundamental prerequisite that is needed prior to scientific acceptance of any study.
* Two peer-reviewed studies have shown that when emergency contraception is available, the incidence of unprotected sex does not increase.<ref>{{cite journal | author = Harper C, Cheong M, Rocca C, Darney P, Raine T | title = The effect of increased access to emergency contraception among young adolescents. | journal = Obstet Gynecol | volume = 106 | issue = 3 | pages = 483-91 | year = 2005 | id = PMID 16135577}}</ref><ref>{{cite journal | author = Norris Turner A, Ellertson C | title = How safe is emergency contraception? | journal = Drug Saf | volume = 25 | issue = 10 | pages = 695-706 | year = 2002 | id = PMID 12167065}}</ref>
*In 1998, Washington was the first state to allow women to get emergency contraception directly from a pharmacist, without first going to a doctor. Doctors and pharmacies collaborated and set up criteria that women were required to meet in order to receive emergency contraception. There were almost 35,600 prescriptions filled from February 1998 until the trial expired in June 2001.

==Footnotes==
<div class="references-small"><references /></div>

==External links==
* [http://www.mapconspiracy.org The Morning-After Pill Conspiracy] &ndash; A grassroots feminist coalition whose members have given out the pill in defiance of the government's refusal to put Plan B over-the-counter. Members of this coalition are involved in a lawsuit with the Center for Reproductive Rights, Tummino v. Crawford, against the FDA alleging sex discrimination.
* [http://www.emergencybirthcontrol.org The Emergency Birth Control Organization] &ndash; Information on Emergency Contraception
* [http://www.arhp.org/healthcareproviders/resources/ecresources/index.cfm Emergency Contraception Resource Center from the Association of Reproductive Health Professionals]
* [http://www.yale.edu/opa/docs/campus/20041104_nejm.pdf The Limits of Conscientious Objection - May Pharmacists Refuse to Fill Prescriptions for Emergency Contraception?] - Julie Cantor,J.D.,and Ken Baum,M.D.,J.D. NEJM, November 4, 2004
* [http://left2right.typepad.com/main/2005/04/the_case_of_the.html The case of the conscientious pharmacist] - Don Herzog
* [http://www.stateaction.org/issues/issue.cfm/issue/EC-CollaborativePractice.xml Center for Policy Alternatives] &ndash; Emergency Contraception Policy Brief and Model Legislation
* [http://ec.princeton.edu Not-2-Late.com, the Emergency Contraception Website]
* [http://www.emergencycontraception.org/asec/index.html American Society for Emergency Contraception]
* [http://www.getthepill.com Get The Pill] &ndash; Online Prescriptions for Emergency Contraception
* [http://www.go2ec.org/ Go 2 EC] &ndash; Emergency Contraception News
* [http://www.plannedparenthood.org/ec/ Planned Parenthood] &ndash; information on emergency contraception
* [http://go2planb.com/ Plan B]
*[http://frwebgate.access.gpo.gov/cgi-bin/getdoc.cgi?dbname=gao&docid=f:d06109.pdf Original documents & Congressional report on FDA refusal of OTC Plan B application]
* [http://americanwomensservices.com/pages/emer_contraception.html Emergency Contraception Information]&ndash; Information on Emergency Contraception
* [http://www.healthpolitics.org/archives.asp?previous=planb Health Politics: Women and Plan B]


{{BirthControl}}

[[Category:Chemical contraception]]
[[Category:Hormonal contraception]]

[[de:Pille danach]]
[[es:Anticonceptivo de emergencia]]
[[fr:Pilule du lendemain]]
[[ko:사후 피임약]]
[[it:Pillola del giorno dopo]]
[[nl:Morning-afterpil]]
[[fi:Jälkiehkäisy]]

Revision as of 17:25, 6 September 2006

Emergency contraception
Background
TypeHormonal (progestin or others) or intra-uterine
First use?
Pregnancy rates (use)
Perfect useIUD under 1%
ECP 11%
Typical use?%
Usage
User remindersPregnancy test required if no period seen after 3 weeks
Clinic reviewRecommended to consider need screen STDs or consider ongoing routine contraceptive options
Advantages and disadvantages
STI protectionNo
Period disadvantagesECP may disrupt next menstrual period by couple days. IUDs may make mustruation heavier and more painful
Weight gainECP:Not from single use
BenefitsIUDs may be subsequently left in place for ongoing contraception
RisksAs per methods
Medical notes
Combined estrogrogen/progestin pills of Yuzpe regimen now superseded by better tolerated and more effective progestin-only pill.
ECP licensed for use within 3 days of unprotected intercourse and IUDs within 5 days.
Wikinews has related news:

Emergency contraception (EC) (also known as Emergency Birth Control (EBC), the morning-after pill, or postcoital contraception) refers to measures, that if taken after sex, may prevent a pregnancy.

Forms of EC include:

  • Emergency contraceptive pill —referred to simply as "emergency contraception," "ECPs," or "ECs", or "morning-after pill" —are hormones that act both to prevent ovulation or fertilisation, or possibly, post-fertilisation, subsequent implantation of a blastocyst (embryo). ECPs are not to be confused with chemical abortion methods that act after implantation has occurred.[1]
  • Intrauterine devices (IUDs) - usually used as a primary contraception method, but sometimes used as emergency contraception.

As opposed to regular methods of contraception, ECs are considered for use in occasional cases only, for example in the event of contraceptive failure. Since they act before implantation, they are considered medically and legally to be forms of contraception. Some pro-life groups define pregnancy as beginning with fertilisation, and therefore consider EC to be an abortifacient. These claims remain controversial; see below.

ECPs

Emergency contraceptive pills (ECPs), are an oral drug containing high doses of the same hormones found in regular oral contraceptive pills, which, when taken after unprotected sexual intercourse, may prevent pregnancy from occurring.

Studies in rats and monkeys have shown that ECPs have no effect on pregnancy rates when taken after ovulation has already occured.[2] When taken before ovulation occurs, ECPs prevent ovulation in 50%[3]-80%[4] of women, and this is the primary way in which they prevent pregnancy. If ovulation occurs despite pre-ovulatory use of EC, there may be changes in certain hormone levels such as progesterone and in the length of the woman's luteal phase.[4] These changes are similar to those found in a woman's first few ovulatory breastfeeding cycles.[5] Because these secondary effects might result in embryos being created, but prevented from implanting in the uterus, they have resulted in some controversy over the use of ECPs.

The phrase "morning-after pill" is a misnomer that is falling out of use due to the fact they are licensed for use up to 72 hours after sexual intercourse. Emergency contraception or "emergency contraceptive pills" is the phrase preferred by the medical community. Unlike chemical abortion, emergency contraception does not end pregnancies and will not harm a developing embryo.

Types of ECPs

Emergency hormonal contraception was available in two main forms: the original version was the combined or Yuzpe regimen which uses large doses of both estrogen and progestin taken as two doses at twelve hour intervals. With this regimen being less effective, and causing more side effects, than the more recently introduced progestin-only method, specific products have been withdrawn (Preven in the United States discontinued May 2004, Schering PC4 in the United Kingdom discontinued October 2001, and Tetragynon in France).

The progestin-only method uses the progestin levonorgestrel in a dose of 1.5 mg, either as two 750 μg doses 12 hours apart, or more recently, as a single dose. This method is now known to be more effective and better tolerated (less nausea or vomiting) than the Yupze method [6], and is available in the U.S. and Canada as Plan B, in the UK as Levonelle, and in France as NorLevo.

"Dedicated products" such as Plan B and Levonelle are specifically designed and marketed as emergency contraceptive pills. It is also possible to obtain the same dosage of hormones, and therefore the same effect, by taking a number of regular progestin-only or combined estrogen-progestin oral contraceptive pills.[7]

The drug mifepristone may be used either as an ECP or as an abortifacient, depending on the dosage given. In the USA it is most commonly used in 200- or 600-mg doses as an abortifacient[8], but in China it is commonly used as an ECP. In this latter role, a 10-mg dose is equally effective; however, as of 2000 the smallest dose available in the USA was 200mg.[9] A review of studies in humans found that the contraceptive effects of the 10-mg dose were due to its effects on ovulation, as with the levonorgestrel ECP.[10]

Effectiveness of ECPs

The effectiveness of emergency contraception is calculated differently than that of ongoing birth control methods. For ongoing methods, the failure rate is defined as the number of pregnancies over one year of use. For EC, the failure rate is defined as the reduction in pregnancy rate from each use of emergency contraception.

Having unprotected intercourse throughout the woman's menstrual cycle is believed to result in a pregnancy rate of 25% per cycle.[11] However, a woman's fertility levels vary drastically throughout the menstrual cycle, so determing the risk of pregnancy from a single act of intercourse is extremely difficult. For this reason, it is challenging to conduct rigorous studies to determine the effectiveness of emergency contraceptive pills.

Despite this difficulty, levonorgestral ECPs have been proven to prevent at least 50% of expected pregnancies in women who take them.[12] It is commonly believed that they actually prevent at least 75% of pregnancies.[13] The effectiveness of emergency contraception is highest when taken within 12 hours of intercourse and declines over time.[14][15][16] The limit of 72 hours is based on a study by the WHO.[6] A subsequent WHO study has suggested reasonable effectiveness continues for up to 120 hours (5 days),[17] however many doctors (particularly in the UK) advise use of an IUD rather than ECPs for emergency contraception between 72 and 120 hours.

The older Yuzpe regime of ECPs is believed to reduce pregnancy rates by about 57%.[15]

ECPs as a birth control method

Emergency contraception cannot be recommended as the main means of birth control because it is not as effective as any ongoing method of contraception. It also does not protect against sexually-transmitted infections. However, it is used by some as a back-up when other means of contraception have failed—for example, if a woman has forgotten to take a birth control pill or when a condom is torn during sex. It is also a first line of treatment option for victims of sexual assault.

Contraindications & Interactions

Emergency contraception pills should not be used by women who are already pregnant because they are not effective then.[18]

Because they contain estrogen, combined estrogen-progestin emergency contraception (Yuzpe regimen) pills should not be used by women with a history of heart attack, stroke, or blood clots, or patients with severe liver disease or the very rare condition of porphyria.[18]

The herbal preparation of St John's wort and enzyme-inducing drugs (e.g. anticonvulsants or rifampicin) may reduce the effectiveness of ECP and a larger dose may be required (Levonorgestrel 1500mcg initial dose and an extra 750mcg after 12 hours)[19] else consider the use of an IUD (see below).

Side effects

The most common side effect of emergency contraception pills are nausea, abdominal pain, fatigue, headache, dizziness, vomiting, and breast tenderness. These side effects are normally resolved within 24 hours. The rate of these effects occurring is less for progestin-only pills when compared to combined pills.

Also common is temporary disruption of the menstrual cycle, which may manifest as early or late periods, spotting or breakthrough-bleeding, and (less commonly) missed periods. The primary mechanism of EC is delaying ovulation. Menstruation occurs on average 14 days after ovulation, so a delayed ovulation will result in a delayed menstruation. Suppression of ovulation may cause anovulatory bleeding, which could manifest as an early period.

More information on side effects is available in the patient information leaflet associated with the brand of EC in question.

Confirmation of Results

A pregnancy test is the only reliable way to confirm whether or not EC has been effective. EC can cause menstrual changes that appear similar to early signs of pregnancy, and some doctors therefore advise all women who take EC to take a pregnancy test afterwards to get confirmation of the results.

Pregnancy tests will not give positive results until after an embryo has implanted, which occurs six to twelve days after ovulation. The most sensitive tests can detect pregnancy the day after implantation, so the earliest a positive result would be seen would be one week after intercourse (assuming intercourse occurred on the day of ovulation). Sperm life of up to five days is considered normal, and less sensitive tests may not detect pregnancy until three to four days after implantation. So a pregnancy test may give false negatives up to three weeks after intercourse (five days between intercourse and ovulation, twelve days between ovulation and implantation, four days between implantation and detectable levels of the pregnancy hormone hCG).

Intrauterine device used for emergency contraception

An alternative to emergency contraceptive pills is the copper-T intrauterine device (IUD) which can be used up to 5 days after unprotected intercourse to prevent pregnancy. Insertion of an IUD is more effective than use of Emergency Contraceptive Pills, reducing the risk of pregnancy following unprotected intercourse by more than 99%. IUDs may then be left in place following the subsequent period to provide contraception for a number of years (3-10 depending upon type and country-specific licensing - see IUD ).[20]

International availability

United Kingdom

As of early 2001, women of age 16 and higher may obtain emergency contraception in the United Kingdom without a prescription. This was challenged by an anti-abortion group, but the High Court of Justice of England and Wales let the rule stand in April 2002.

United States

Since December 2000, the official policy of the American Medical Association (AMA) has been to support Food and Drug Administration (FDA) approval of over-the-counter (OTC) access to emergency contraception without a prescription in the U.S.[21] The AMA, the American Academy of Family Physicians, the American College of Obstetricians and Gynecologists, the American Academy of Pediatrics, and other leading U.S. medical organizations have passed resolutions and petitioned the FDA to allow OTC access.[22]

On December 16, 2003, an advisory committee to the FDA recommended that Plan B be made available over the counter.[23] The committee voted 23 to 4 to recommend Plan B be switched from prescription to OTC status. The committee unanimously voted 28 to 0 that the data demonstrated Plan B was safe for use in an OTC setting, and unanimously voted 28 to 0 that there was not evidence that OTC availability of Plan B leads to substitution of emergency contraception for regular use of other contraceptive methods.[24]

However, in May of 2004 the FDA refused this strong recommendation and prohibited over-the-counter sale. The FDA claimed that this was due to limited experimental data on the effects of such pills on girls under 16 years of age, but critics have accused the FDA of basing the decision on political pressure. [25] One year later, a new application from the makers of Plan B requested over-the-counter status for women aged 16 and older, but the January 2005 deadline for the FDA decision on this application has come and gone without a decision. The FDA had more pledged to rule on the application by September 1, 2005, but this deadline has been extended for at least 60 days. Barr re-filed its application for Plan B for OTC access just to those 18 and up while those under 18 would still need a prescription. Bush stated that he would support Eshenbach's decision to approve Barr's application as long as minors did not get the drug without a prescription.[26]. The FDA announced on August 24, 2006 that this emergency contraception would be available to those over 18 years of age over-the-counter.[27] Before this decision, eight states (California, Washington, Alaska, Hawaii, New Mexico, Maine, New Hampshire and Massachusetts) passed laws permitting trained pharmacists to dispense emergency contraception without a doctor's prescription.

In a number of instances across the United States, pharmacists have refused to give women emergency contraception even with a legal prescription. These pharmacist refusals have created great controversy. Pharmacists who believe that emergency contraception is equivalent to abortion, or who, for personal moral or religious reasons oppose the use of birth control pills for unmarried women, or at all, have in a number of instances across the United States asserted a right of conscience to refuse to fill those prescriptions. The American Pharmacists Association has proposed conscience clauses or refusal clauses that would allow pharmacists to opt out of filling prescriptions they found morally offensive as long as they referred women to other pharmacists who would fill the prescription.

Women's rights and pro-choice organizations have expressed concern that in many parts of the country there may not be reasonable alternatives if a prescription isn't filled, that having a prescription refused could be both intimidating and upsetting to women who are likely to be in a crisis situation, and that there is a short window of time during which EC is effective--making delays possible cancellations of the option. Advocates for women's use of ECs say that conscience clauses are often overly broad, and that women have a right to medically appropriate, effective, and legal reproductive health services regardless of the medical professional's personal beliefs.[28]

On August 24, 2006, the Food and Drug Administration approved the morning-after pill for use without a prescription in the United States, but only for women over 18 with proof of ID. Girls aged 17 and under must have a doctor's note in order to procure the morning-after pill. Plan B will not be available in gas stations or convenience stores as are some other OTC medications, and sales will be limited to locations with a pharmacist on staff.

Canada

In May 2004, Canada's Health Minister announced that Plan B would soon become available from pharmacists in all provinces without a prescription. This occurred on April 28, 2005. The new system would still require the person to purchase the pills directly from the pharmacist.

France

In January 2000, France decided to dispense emergency contraception in junior and high schools by school nurses without prescription, because of high rates of undesired pregnancies among teenaged girls; after strong opposition from the Roman Catholic Church, and much debate around the fact the teenager could later suffer from the doubt of not knowing whether fertilization had occurred or not, the decision was overruled by a court in July 2000. The French parliament changed the relevant law in October 2000 and now school nurses are again able to dispense the drugs. The emergency contraception pill NorLevo is now available in France without prescription, without parent authorization, and free of charge for teenagers under the age of 18 since January 9, 2002.

Other Countries

Emergency contraception is available without prescription in the following countries: Albania, Australia, Belgium, Benin, Bulgaria, Cameroon, Canada, China, Colombia, Congo, Croatia, Denmark, Estonia, Finland, France, French Polynesia, Gabon, Ghana, Greece, Guinea-Conakry, Iceland, India, Israel, Ivory Coast, Jamaica, Latvia, Lithuania, Madagascar, Mali, Mauritania, Mauritius, Morocco, Mexico, Netherlands, New Zealand, Norway, Portugal, Romania, Senegal, South Africa, Sri Lanka, Sweden, Switzerland, Togo, Tunisia, Turkey, the United Kingdom and Uruguay.

In Ireland and Italy, it is available without restriction, but is not available over-the counter and requires a visit to a doctor of family-planning clinic. [29]

Controversy

Emergency contraception, implantation, and abortion politics

A number of studies in the 1970s and 80s concluding that emergency contraception could cause changes in the endometrium,[30] and thus preventing implantation of an early stage embryo in the uterus, led many pro-life advocates, who widely believe that pregnancy begins at fertilisation, to oppose ECPs as an abortifacient.

In recent years, however, especially in light of U.S. controversy over this possibility, the scientific community has begun to critically reevaluate the claim, introducing doubt into the argument that ECPs prevent implantation. Recent studies in rats and monkeys have shown that post-ovulatory use of ECPs do not have any effect on pregnancy rates.[2] Studies in humans have shown that the rate of ovulation suppression is approximately equal to the effectiveness of emergency contraceptive pills,[4] suggesting that might be the only mechanism by which they prevent pregnancy.

However, these studies have also shown that, in women who ovulate despite taking ECP before ovulation, there are changes in certain hormones such as progesterone and in the length of their luteal phase.[4] These secondary changes might inhibit implantation in cases where fertilization occurs despite ECP use. Because of the difficulty of studying pre-implanted embryos inside the uterus and fallopian tubes, both sides of this debate concede that completely proving or disproving the theory may be impossible.[31][2]

The Food and Drug Administration recently stopped its practice [32] of referring to all three mechanisms in its publications on emergency contraception. [33] However, the approved box design for Plan B, an emergency contraceptive approved for over-the-counter sale in the United States, will still carry a notification that it may prevent implanation. [34]

When used as a regular method of contraception, IUDs have been proven to act primarily through spermicidal and ovicidal mechanisms. However, it is theoretically possible that these same mechanisms are also harmful to pre-implanted embryos.[35] The primary mechanism of action of IUDs that are used as emergency contraception is not known.

In any case, emergency contraceptives such as Yuzpe regimen or Plan B are not to be confused with high doses of mifepristone (also known as Mifeprex and RU-486), an abortifacient which is taken after implantation and designed specifically to abort the fetus. Emergency contraception will have no effect if taken after implantation.

See also: Beginning of pregnancy controversy

A Massachusetts law that went into effect on 14 December, 2005, requires all hospitals in the state to provide emergency contraception to any "female rape victim of childbearing age" [36] including Catholic Hospitals who oppose the provision of emergency contraception. In a letter criticizing the joint UN/WHO Inter-agency Field Manual on Reproductive Health in Refugee Situations, the Catholic Church explains its belief that emergency contraception, along with IUDs and hormonal contraception, cannot be considered "solely contraceptive because in the case of effective fertilisation a chemical abortion would be carried out during the first days of pregnancy."[37] The Catholic position on family planning is explained further in Ethical and Religious Directives for Catholic Health Care Services.[38] Because of this expressed moral stance against emergency contraception, the Massachusetts Catholic Conference opposed this law, stating interference with religious freedom.

  • More than 300,000 women are sexually assaulted each year in the US.[39] An estimated 25,000 of these sexual assaults will result in pregnancy. About 22,000 of these pregnancies could be prevented if all women who were raped had easy access to emergency contraception.[40]
  • A Guttmacher Institute journal reported that:
    • Abortions because of rape account for less than one percent of all annual abortions. [41]
    • nearly one half of America's 6.4 million annual pregnancies are accidental[42]
    • unintended pregnancies result in 1.3 million abortions annually[42]
  • A study in the UK reported that "the shift towards greater promotion of emergency birth control appears to have (...) worsened the impact of STI rates since 2000."[43] It should be noted that the business professor who wrote this paper has yet to publish this paper in a peer reviewed journal. Peer review is a fundamental prerequisite that is needed prior to scientific acceptance of any study.
  • Two peer-reviewed studies have shown that when emergency contraception is available, the incidence of unprotected sex does not increase.[44][45]
  • In 1998, Washington was the first state to allow women to get emergency contraception directly from a pharmacist, without first going to a doctor. Doctors and pharmacies collaborated and set up criteria that women were required to meet in order to receive emergency contraception. There were almost 35,600 prescriptions filled from February 1998 until the trial expired in June 2001.

Footnotes

  1. ^ A minority view within the medical community, along with many pro-life advocates, argue for a different definition of pregnancy, see Controversy section for more detail.
  2. ^ a b c Article "Emergency Contraception's Mode of Action Clarified". Population Briefs. 11 (2). Population Council. May 2005. Retrieved 2006-08-27. {{cite journal}}: Check |url= value (help), which cites:
    Mena P (2005). "Post-coital administration of levonorgestrel and post-fertilization events in the new-world monkey Cebus apella". Hum Reprod. 20 (5): 1428, author reply 1428-9. PMID 15845601.
    Müller A, Llados C, Croxatto H (2003). "Postcoital treatment with levonorgestrel does not disrupt postfertilization events in the rat". Contraception. 67 (5): 415–9. PMID 12742567.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  3. ^ Croxatto HB, Brache V, Pavez M, Cochon L, Forcelledo ML, Alvarez F, Massai R, Faundes A, Salvatierra AM (2004). "Pituitary-ovarian function following the standard levonorgestrel emergency contraceptive dose or a single 0.75-mg dose given on the days preceding ovulation". Contraception. 70 (6): 442–50. PMID 15541405.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  4. ^ a b c d Durand M, del Carmen Cravioto M, Raymond EG, Duran-Sanchez O, De la Luz Cruz-Hinojosa M, Castell-Rodriguez A, Schiavon R, Larrea F (2001). "On the mechanisms of action of short-term levonorgestrel administration in emergency contraception". Contraception. 64 (4): 227–34. PMID 11747872.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  5. ^ Díaz S, Cárdenas H, Brandeis A, Miranda P, Salvatierra A, Croxatto H (1992). "Relative contributions of anovulation and luteal phase defect to the reduced pregnancy rate of breastfeeding women". Fertil Steril. 58 (3): 498–503. PMID 1521642.{{cite journal}}: CS1 maint: multiple names: authors list (link)
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  16. ^ Reviewing editorial from the BMJ 2003;326:775-776 ( 12 April ) Editorial
  17. ^ Low dose mifepristone and two regimes of levonorgestrel for emergency contraception: a WHO multicentre randomised trial. Lancet 2002; 360: 1803-1810 PMID 12480356
  18. ^ a b American Academy of Pediatrics Committee on Adolescence (2005). "Emergency contraception". Pediatrics. 116 (4): 1026–35. PMID 16147972.
  19. ^ For women who are using liver enzyme inducing drugs, what dose of progestogen-only emergency contraception is advised? PDF members response 916 Faculty of Family Planning and Reproductive Health Care - Clinical Effectiveness Unit
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  26. ^ Bush supports limits on morning-after pill
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  36. ^ Commonwealth of Massachusetts Chapter 91 of the Acts of 2005. "An Act Providing Timely Access to Emergency Contraception." Enacted September 15, 2005. Accessed April 28, 2006.
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  39. ^ Tjaden, Patricia (2006). "Extent, Nature, and Consequences of Rape Victimization: Findings From the National Violence Against Women Survey" (PDF). National Institute of Justice. Retrieved 2006-08-23. {{cite journal}}: Cite journal requires |journal= (help); Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)
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  41. ^ Finer, Lawrence B. (2005). "Reasons U.S. Women Have Abortions: Quantitative and Qualitative Perspectives" (PDF). Perspectives on Sexual and Reproductive Health. 37 (3): 110–118. PMID 16150658. Retrieved 2006-08-23. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)
  42. ^ a b Finer, Lawrence B. (2006). "Disparities in Rates of Unintended Pregnancy in the United States, 1994 and 2001". Perspectives on Sexual and Reproductive Health. 38 (2). PMID 16772190. Retrieved 2006-08-23. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)
  43. ^ Paton, David. "Random Behavior or Rational Choice? Family Planning, Teenage Pregnancy, and STIs. (2003).
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  45. ^ Norris Turner A, Ellertson C (2002). "How safe is emergency contraception?". Drug Saf. 25 (10): 695–706. PMID 12167065.


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