Abortion–breast cancer hypothesis explained

The abortion–breast cancer hypothesis posits that having an induced abortion can increase the risk of getting breast cancer.[1] This hypothesis is at odds with mainstream scientific opinion and is rejected by major medical professional organizations;[1] [2] despite this, it continues to be widely propagated as pseudoscience, typically in service of an anti-abortion agenda.

In early pregnancy, hormone levels increase, leading to breast growth.[3] The hypothesis proposes that if this process is altered by an abortion, then more immature cells could be left behind, and that these immature cells could increase the risk of breast cancer over time.[4]

The abortion–breast cancer hypothesis has been the subject of extensive scientific inquiry, and the scientific community has concluded that abortion does not cause breast cancer;[1] [2] and that breast cancer should not be a concern for women who are having a miscarriage or considering having an abortion. This consensus is supported by major medical bodies, including the World Health Organization,[5] [6] the U.S. National Cancer Institute,[7] [8] the American Cancer Society,[9] the American Congress of Obstetricians and Gynecologists,[10] the Royal College of Obstetricians and Gynaecologists,[11] the German Cancer Research Center,[12] and the Canadian Cancer Society.[13]

Some anti-abortion activists have continued to advance a discredited causal link between abortion and breast cancer. In the United States, they have advanced state legislation that in several states requires health care providers to present abortion as a cause of breast cancer when counseling women who are seeking abortion. This political intervention culminated when the George W. Bush administration altered the National Cancer Institute website to suggest that abortion might cause breast cancer.[14] In response to public concern over this intervention, the NCI convened a 2003 workshop bringing together over 100 experts on the issue. This workshop concluded that while some studies reported a statistical correlation between breast cancer and abortion,[15] [16] [17] the strongest scientific evidence[18] from large prospective cohort studies[19] [20] demonstrates that abortion is not associated with an increase in breast cancer risk,[21] and that the positive findings were likely due to response bias.[22]

The ongoing promotion of a link between abortion and breast cancer is seen by others as part of the anti-abortion "woman-centered" strategy against abortion.[23] [24] Anti-abortion groups maintain they are providing information necessary for legally required informed consent,[25] a concern shared by some politically conservative politicians.[26] The abortion–breast cancer issue remains the subject of political controversy.[27]

Views of medical organizations

Major medical organizations which have analyzed data on abortion and breast cancer have uniformly concluded that abortion does not cause breast cancer. These organizations include the World Health Organization, the U.S. National Cancer Institute, the American Cancer Society, the American Congress of Obstetricians and Gynecologists, the Royal College of Obstetricians and Gynaecologists, the German Cancer Research Center, and the Canadian Cancer Society.[5] [11] [13] [21]

Proponents

Joel Brind, a faculty member at Baruch College in the Department of Natural Sciences,[32] is the primary advocate of an abortion - breast cancer ("ABC") link. Brind is strongly anti-abortion and began lobbying politicians with the claim that abortion caused breast cancer in the early 1990s. Brind found that his lobbying efforts were not taken seriously because he had not published his findings in the peer-reviewed medical literature. He therefore collaborated with two anti-abortion physicians and a statistician to publish a 1996 article in the Journal of Epidemiology and Community Health,[33] arguing that induced abortion was a risk factor for breast cancer. The statistician who collaborated with Brind later stated of their findings: "I have some doubts. I don't think the issue has been resolved. When we were talking about the conclusions, he [Brind] wanted to make the strongest statements. I tried to temper them a little bit, but Dr. Brind is very adamant about his opinion."

Brind's paper was criticized in the Journal of the National Cancer Institute for ignoring the role of response bias and for a "blurring of association with causation."[34] The amount of attention the study received prompted a cautionary editorial by a JECH editor.[35] With the appearance of larger studies contradicting Brind's finding, Brind failed to convince the scientific community that abortion caused breast cancer. In 2003, Brind was invited to the NCI workshop on abortion and breast cancer, where he was the only one to formally dissent from the workshop's finding that there is no link between the two. Brind blames the lack of support for his findings on a conspiracy, arguing that the NCI and other major medical organizations are engaged in a "cover-up" for the purpose of "protecting the abortion industry".

Proposed mechanism

In early pregnancy, levels of estrogen, progesterone, and estradiol increase, leading to breast growth in preparation for lactation. Proponents speculate that if this process is interrupted by an abortion or miscarriage—before full maturity (differentiation) in the third trimester—then more immature cells could be left than there were prior to the pregnancy. These immature cells could then be exposed to carcinogens and hormones over time, resulting in a greater potential risk of breast cancer. This mechanism was first proposed and explored in rat studies conducted in the 1980s.[36] [37] [38]

Breast tissue contains many lobes (segments) and these contain lobules which are groups of breast cells. There are four types of lobules:

During early pregnancy, type 1 lobules quickly become type 2 lobules because of changes in estrogen and progesterone levels. Maturing into type 3 and then reaching full differentiation as type 4 lobules requires an increase of human placental lactogen (hPL) which occurs in the last few months of pregnancy. According to the abortion - breast cancer hypothesis, if an abortion were to interrupt this sequence then it could leave a higher ratio of type 2 lobules than existed prior to the pregnancy.[39] Russo and Russo have shown that mature breast cells have more time for DNA repair with longer cell cycles, accounting for the slightly reduced risk of breast cancer for parous women against the baseline risk for women who have never conceived and those who have conceived and terminated their pregnancies.[36]

Later on, Russo et al. found that placental human chorionic gonadotropin (hCG) induces the synthesis of inhibin by the mammary epithelium.[40] [41] Bernstein et al. independently observed a reduced breast cancer risk when women were injected with hCG for weight loss or infertility treatment.[42] Contrary to the ABC hypothesis, Michaels et al. hypothesize since hCG plays a role in cellular differentiation and may activate apoptosis, as levels of hCG increase early on in human pregnancy, "an incomplete pregnancy of short duration might impart the benefits of a full-term pregnancy and thus reduce the risk of breast cancer."[20]

History

The first study involving statistics on abortion and breast cancer was a broad study in 1957 examining common cancers in Japan.[27] The researchers were cautious about drawing any conclusions from their unreliable methodologies. During the 1960s several studies by Brian MacMahon et al. in Europe and Asia touched on a correlation between abortion and breast cancer. Their 1973 paper published in the Journal of the National Cancer Institute inaccurately[27] concluded that "where a relationship was observed, abortion was associated with increased, not decreased, risk."[43] Research relevant to the current ABC discussion focuses on more recent large cohort studies, a few meta-analyses, many case-control studies, and several early experiments with rats.

Rat models

Russo & Russo from the Fox Chase Cancer Center in Philadelphia conducted a study in 1980 examining the proposed correlation between abortion and breast cancer. While analysing the effects of the carcinogen 7,12-Dimethylbenz(a)anthracene (DMBA) on the DNA labeling index (DNA-LI) in terminal end buds (TEBs), terminal ducts (TDs) and alveolar buds (ABs) of Sprague-Dawley rats in various stages of reproductive development, they found that rats who had interrupted pregnancies had no noticeable increase in risk for cancer.[36] However, they did find that pregnancy and lactation provided a protective measure against various forms of benign lesions, such as hyperplastic alveolar nodules and cysts. While results did suggest that rats who had interrupted pregnancies might be subject to "similar or even higher incidence of benign lesions" than virgin rats, there was no evidence to suggest that abortion would result in a higher incidence of carcinogenesis. A more thorough examination of the phenomenon was conducted in 1982, confirming the results.[37] A later study in 1987 further explained their previous findings.[38] After differentiation of the mammary gland resulting from a full-term pregnancy of the rat, the rate of cell division decreases and the cell cycle length increases, allowing more time for DNA repair.[38] [44]

Despite the fact that the Russos' studies found similar risk rates between virgin and pregnancy interrupted rats, their research would be used to support the contention that abortion created a greater risk of breast cancer for the next twenty years.[45] However, because rats do not exhibit naturally occurring breast cancer, the extrapolation of these results to human abortion and breast cancer is viewed as dubious.[46]

Epidemiological evidence

The results of prospective cohort studies on the relationship between abortion and breast cancer have been consistently negative. Such studies are considered more reliable than retrospective studies and case-control studies.[47] [48] The positive association between abortion and breast cancer risk observed in case-control studies may be accounted for by recall bias.[49]

In 1996, Brind et al. published a meta-analysis of 23 studies which reported a positive association existed between induced abortion and breast cancer risk. The authors estimated the relative risk of breast cancer among women who had had an induced abortion to be 1.3, compared to women who had not had an abortion.[50] It was criticized by other researchers for multiple reasons, including allegations that it failed to account for publication bias (positive studies tend to be more likely to be published).[51] The meta-analysis was also criticized because the studies it included were almost all case-control studies, which are susceptible to recall bias, and for which it is difficult to select an appropriate control group.[52]

In 1997, Wingo et al. reviewed 32 studies on the abortion-breast cancer relationship and concluded that the results of studies on this subject were too inconsistent to allow for definitive conclusions, for either induced or spontaneous abortions.[53]

A 2004 analysis of data from 53 studies involving 83,000 women with breast cancer reported no increased risk among women who had had either an induced or spontaneous abortion. The relative risk of breast cancer for women who had a spontaneous abortion in this analysis was 0.98, and that for induced abortion was 0.93.[54]

A 2015 systematic review and meta-analysis of prospective studies found insufficient evidence to support an association between induced or spontaneous abortion and an increased risk of breast cancer.[55]

Politicization

By the late 1980s, national politicians recognized that a focus on reducing access to abortion was not a winning political strategy. Some anti-abortion activists grew more aggressive and violent in the face of political abandonment, culminating with the murder of Dr. David Gunn in 1993 and the passage of the Freedom of Access to Clinic Entrances Act in 1994. With direct action discredited, anti-abortion organizations, including the National Right to Life Committee, came to the forefront of the movement. These focused on legal tactics, including lobbying against late-term abortions and access to mifepristone and demanding legislation based on the purported ABC link.[27] More recently, anti-abortion organizations have turned to lobbying to increase obstacles to abortion, such as mandated counseling, waiting periods, and parental notification,[56] and some feel that anti-abortion advocates treat ABC as simply another tactic in their campaign against abortion.[24] [57] There have been ongoing and incremental legal challenges to abortion in the United States by anti-abortion groups.[58] In 2005, a Canadian anti-abortion organization put up billboards in Alberta with large pink ribbons and the statement: "Stop the Cover-Up", in reference to the ABC hypothesis.[59] The Canadian Breast Cancer Foundation was concerned by the misrepresentation of the state of scientific knowledge on the subject.[60]

The continued focus on the ABC hypothesis by anti-abortion groups has fostered a confrontational political environment. Anti-abortion advocates and scientists alike have responded with criticisms.[27] [19] [34] The claims by anti-abortion advocates are sometimes referred to as pseudoscience.[61] [62] [63]

During the late 1990s, several members of the United States Congress became involved in the ABC issue. In a 1998 hearing on cancer research, U.S. Representative Tom Coburn accused the National Cancer Institute of misleading the public by selectively releasing data.[64] In 1999, shortly after the House debated FDA approval of the abortion drug mifepristone, U.S. Representative Dave Weldon wrote a "Dear Colleague" letter, enclosing an article from John Kindley. In it, Weldon expressed concern that the majority of studies indicated a possible ABC link and that politicization was "preventing vital information from being given to women."[26]

, abortion counseling materials in Alaska, Kansas, Mississippi, Oklahoma, and Texas incorrectly assert a possible link between abortion and breast cancer, while Minnesota materials correctly report no link.[65] Similar legislation requiring notification has also been introduced in 14 other states.[66] An editor for the American Journal of Public Health expressed concern that these bills propose warnings that do not agree with established scientific findings.[67]

Bioethicist Jacob M. Appel argues that the mandatory disclosure statutes might be unconstitutional on "rational basis" grounds. Childbirth is significantly more dangerous than abortion, data that is not required in any disclosure law but which is necessary for a meaningful understanding of risks. According to Appel, "[i]f the roughly fifty million abortions that have occurred in the United States since Roe v. Wade had all ended in full-term deliveries, approximately five hundred additional women would have died during childbirth."[68]

In May 2017, President Donald Trump appointed Charmaine Yoest, an anti-abortion activist and proponent of the abortion-breast cancer link, to the post of assistant secretary for public affairs in the Department of Health And Human Services.[69]

National Cancer Institute

The National Cancer Institute (NCI) has been a target of the anti-abortion movement for the conclusions presented on its website.[27] A report from the Committee on Oversight and Government Reform found that in November 2002 the Bush administration had altered the NCI website. The previous NCI analysis had concluded that, while some question regarding an association between abortion and breast cancer existed prior to the mid-1990s, a number of large and well-regarded studies had resolved the issue in the negative. The Bush administration removed this analysis and replaced it with the following:

This alteration, which suggested that there was scientific uncertainty on the ABC issue, prompted an editorial in The New York Times describing it as an "egregious distortion" and a letter to the Secretary of Health and Human Services from members of Congress.[14] [70] In response to the alteration the NCI convened a three-day consensus workshop entitled Early Reproductive Events and Breast Cancer on 24–26 February 2003. The workshop concluded that induced abortion does not increase a woman's risk of breast cancer, and that the evidence for this had been well established.[21] Afterwards, the director of epidemiology research for the American Cancer Society stated, "[t]his issue has been resolved scientifically ... This is essentially a political debate."[14]

Brind was the only attendee at the workshop to file a dissenting opinion as a minority report criticizing the conclusions.[71] He contends the workshop evidence and findings were overly controlled by its organizers and that the time allotted was too short for a thorough review of the literature.[71]

North Dakota lawsuit

In January 2000, Amy Jo Kjolsrud (née Mattson), an anti-abortion counselor, sued the Red River Women's Clinic in Fargo, North Dakota, alleging false advertising.[72] The suit, Kjolsrud v. MKB Management Corporation, alleged that the clinic was misleading women by distributing a brochure quoting a National Cancer Institute fact sheet on the ABC hypothesis. The brochure stated:

The case was originally scheduled for 11 September 2001, but was delayed as a result of the terrorist attacks. On 25 March 2002, the trial began. After four days of testimony, Judge Michael McGuire ruled in favor of the clinic.

Linda Rosenthal, an attorney from the Center for Reproductive Rights characterized the decision as a rejection of "scare tactics".[73] John Kindley, one of the lawyers representing Kjolsrud, highlighted the "individual's right to self-determination".[74] Kindley also wrote a 1998 Wisconsin Law Review article outlining the viability of medical malpractice lawsuits based upon not informing patients considering abortion about the ABC hypothesis.[75]

The decision was appealed and on 23 September 2003 the North Dakota Supreme Court ruled that Kjolsrud did not have standing and affirmed the lower court ruling dismissing the action. The appeal said that Kjolsrud had not read the materials, and that after the lawsuit was filed, the brochures were updated to refute the breast cancer link, citing the National Cancer Institute.[76]

External links

Notes and References

  1. Melbye . M. . Wohlfahrt . J. . Olsen . J. H. . Frisch . M. . Westergaard . T. . Helweg-Larsen . K. . Andersen . P. K. . 1997-01-09 . Induced abortion and the risk of breast cancer . The New England Journal of Medicine . 336 . 2 . 81–85 . 10.1056/NEJM199701093360201 . 0028-4793 . 8988884. free .
  2. Web site: Abortion and Cancer Risk . 2023-02-11 . www.cancer.org . en . 23 February 2023 . https://web.archive.org/web/20230223021352/https://www.cancer.org/healthy/cancer-causes/medical-treatments/abortion-and-breast-cancer-risk.html . live .
  3. Web site: Breast changes from pregnancy to weaning . 2023-02-11 . Medela . en . 11 February 2023 . https://web.archive.org/web/20230211130414/https://www.medela.com/breastfeeding/mums-journey/breast-changes-pregnancy-to-weaning . live .
  4. Russo J, Russo I . Susceptibility of the mammary gland to carcinogenesis. II. Pregnancy interruption as a risk factor in tumor incidence . Am J Pathol . 100 . 2 . 505–506 . 1980 . 6773421 . 1903536 . In contrast, abortion is associated with increased risk of carcinomas of the breast. The explanation for these epidemiologic findings is not known, but the parallelism between the DMBA-induced rat mammary carcinoma model and the human situation is striking. [...] Abortion would interrupt this process, leaving in the gland undifferentiated structures like those observed in the rat mammary gland, which could render the gland again susceptible to carcinogenesis..
  5. Web site: WHO – Induced abortion does not increase breast cancer risk . 11 January 2011 . who.int . https://web.archive.org/web/20110113001029/http://www.who.int/mediacentre/factsheets/fs240/en/index.html . 13 January 2011 . dead.
  6. Book: . Safe abortion: technical and policy guidance for health systems . 2012 . 2nd . 9789241548434 . Sound epidemiological data show no increased risk of breast cancer for women following spontaneous or induced abortion. . 49 .
  7. Web site: Abortion, Miscarriage, and Breast Cancer Risk. 20 February 2003. National Cancer Institute. 11 January 2011. https://web.archive.org/web/20101221084337/http://www.cancer.gov/cancertopics/factsheet/Risk/abortion-miscarriage. 21 December 2010 . live.
  8. Web site: Politics & Science – Investigating the State of Science Under the Bush Administration . 14 April 2008 . oversight.house.gov . https://web.archive.org/web/20091104194534/http://oversight.house.gov/features/politics_and_science/example_breast_cancer.htm . 4 November 2009 . dead .
  9. Web site: Is Abortion Linked to Breast Cancer?. American Cancer Society. 11 January 2011. https://web.archive.org/web/20110131054059/http://www.cancer.org/Cancer/BreastCancer/MoreInformation/is-abortion-linked-to-breast-cancer. 31 January 2011 . live.
  10. Committee on Gynecologic . Practice. ACOG Committee Opinion No. 434: induced abortion and breast cancer risk . Obstetrics and Gynecology . 113 . 6 . 1417–8 . June 2009 . 19461458 . 10.1097/AOG.0b013e3181ac067d . free .
  11. Web site: The Care of Women Requesting Induced Abortion . 9 . Royal College of Obstetricians and Gynaecologists . 29 June 2008 . Induced abortion is not associated with an increase in breast cancer risk. . dead . https://web.archive.org/web/20130727105037/http://www.rcog.org.uk/files/rcog-corp/uploaded-files/NEBAbortionSummary.pdf . 27 July 2013.
  12. Web site: Krebsmythen: Kein Grund zur Sorge . German Cancer Research Center . 4 December 2013 . 9 September 2014 . de . Cancer myths: no reason for concern . 4 December 2020 . https://web.archive.org/web/20201204151940/http://www.krebsinformationsdienst.de/vorbeugung/risiken/mythen.php#inhalt9 . live .
  13. Web site: Canadian Cancer Society's perspective on abortion and breast cancer . Canadian Cancer Society . 28 October 2013 . 9 September 2014 .
  14. Web site: Politics & Science in the Bush Administration . 4 November 2007 . oversight.house.gov. https://web.archive.org/web/20121215150603/http://democrats.oversight.house.gov/images/stories/documents/20080130103545.pdf. 15 December 2012.
  15. Howe H, Senie R, Bzduch H, Herzfeld P . Early abortion and breast cancer risk among women under age 40 . Int J Epidemiol . 18 . 2 . 300–4 . 1989 . 2767842 . 10.1093/ije/18.2.300.
  16. Journal of the National Cancer Institute. 2 November 1994. 86. 21. 1584–92. Risk of breast cancer among young women: relationship to induced abortion. 7932822. Daling JR, Malone KE, Voigt LF, White E, Weiss NS . 10.1093/jnci/86.21.1584.
  17. Daling JR . Risk of breast cancer among white women following induced abortion . Am. J. Epidemiol. . 144 . 4 . 373–80 . 1996 . 8712194 . Brinton LA . Voigt LF . 3 . Weiss . NS . Coates . RJ . Malone . KE . Schoenberg . JB . Gammon . M. 10.1093/oxfordjournals.aje.a008938 . free .
  18. Web site: Weird Science . Ms. Magazine . 14 October 2008 . https://web.archive.org/web/20080517034613/http://www.msmagazine.com/june03/jordan.asp . 17 May 2008 . dead .
  19. Melbye M, Wohlfahrt J, Olsen J, Frisch M, Westergaard T, Helweg-Larsen K, Andersen P . Induced abortion and the risk of breast cancer . N Engl J Med . 336 . 2 . 81–5 . 1997 . 8988884 . 10.1056/NEJM199701093360201. free .
  20. Michels KB, Xue F, Colditz GA, Willett WC . Induced and spontaneous abortion and incidence of breast cancer among young women: a prospective cohort study . Arch. Intern. Med. . 167 . 8 . 814–20 . 2007 . 17452545 . 10.1001/archinte.167.8.814.
  21. Web site: Summary Report: Early Reproductive Events Workshop – National Cancer Institute . 4 November 2007 . cancer.gov . 20 February 2003 . 13 April 2015 . https://web.archive.org/web/20150413140159/http://www.cancer.gov/cancertopics/causes/ere/workshop-report . live .
  22. Web site: Breast Cancer Prevention. 15 July 2011. National Cancer Institute. 20 August 2011. https://web.archive.org/web/20110727212335/http://www.cancer.gov/cancertopics/pdq/prevention/breast/HealthProfessional/page2. 27 July 2011 . live.
  23. Web site: Research and Destroy . 14 April 2008 . washingtonmonthly.com . Chris Mooney . 2004 . dead . https://web.archive.org/web/20080404034430/http://www.washingtonmonthly.com/features/2004/0410.mooney.html . 4 April 2008.
  24. Web site: THE PRO-CHOICE ACTION NETWORK . 4 November 2007 . prochoiceactionnetwork-canada.org. https://web.archive.org/web/20071011174702/http://prochoiceactionnetwork-canada.org/articles/abclink.shtml. 11 October 2007 . live.
  25. Web site: Women's Health after Abortion . 14 April 2008 . deveber.org . https://web.archive.org/web/20080314204201/http://www.deveber.org/text/whealth.html#eighteen . 14 March 2008 . dead.
  26. Web site: Weldon Letter . 4 November 2007 . abortionbreastcancer.com . https://web.archive.org/web/20071023193043/http://www.abortionbreastcancer.com/weldon_letter.htm . 23 October 2007 . dead .
  27. Jasen P . Breast cancer and the politics of abortion in the United States . Med Hist . 49 . 4 . 423–44 . 2005 . 16562329 . 1251638 . 10.1017/S0025727300009145.
  28. Web site: Is Abortion Linked to Breast Cancer? . 8 September 2014 . 19 June 2014 . . 5 June 2011 . https://web.archive.org/web/20110605204701/http://www.cancer.org/Cancer/BreastCancer/MoreInformation/is-abortion-linked-to-breast-cancer . dead .
  29. Web site: National Cancer Institute (NCI) | National Institutes of Health (NIH) . Nih.gov . 2015-10-14 . 2015-12-17 . 5 October 2015 . https://web.archive.org/web/20151005004939/http://www.nih.gov/about/almanac/organization/NCI.htm . live .
  30. Web site: . Briefing note—Scientific Information on Abortion . 29 January 2008 . 9 September 2014 . 9 September 2014 . https://web.archive.org/web/20140909031047/http://www.rcog.org.uk/what-we-do/campaigning-and-opinions/briefings-and-qas-/human-fertilisation-and-embryology-bill/brie-4 . live .
  31. Web site: The Care of Women Requesting Induced Abortion . https://web.archive.org/web/20120529004416/http://www.rcog.org.uk/files/rcog-corp/Abortion%20guideline_web_1.pdf . dead . 2012-05-29 . November 2011 . 9 September 2014 . .
  32. Web site: Joel Brind, Department of Natural Sciences. Baruch College. 29 June 2008. 23 September 2015. https://web.archive.org/web/20150923182719/http://www.baruch.cuny.edu/wsas/departments/natural_science/faculty/brind.html. live.
  33. J Epidemiol Community Health . Induced abortion as an independent risk factor for breast cancer: a comprehensive review and meta-analysis. . Brind J, Chinchilli VM, Severs WB, Summy-Long J . 50 . 5 . 1996 . 481–96 . 8944853 . 1060338 . 10.1136/jech.50.5.481.
  34. Weed DL, Kramer BS . Induced abortion, bias, and breast cancer: why epidemiology hasn't reached its limit . J. Natl. Cancer Inst. . 88 . 23 . 1698–700 . 1996 . 8943995 . 10.1093/jnci/88.23.1698.
  35. Donnan S . Abortion, breast cancer, and impact factors—in this number and the last . J Epidemiol Community Health . 50 . 6 . 605 . December 1996 . 9039374 . 1060372 . 10.1136/jech.50.6.605 .
  36. Russo J, Russo I . Susceptibility of the mammary gland to carcinogenesis. II. Pregnancy interruption as a risk factor in tumor incidence . Am J Pathol . 100 . 2 . 497–512 . 1980 . 6773421 . 1903536.
  37. Russo J, Tay L, Russo I . Differentiation of the mammary gland and susceptibility to carcinogenesis . Breast Cancer Res Treat . 2 . 1 . 5–73 . 1982 . 6216933 . 10.1007/BF01805718. 22657169 .
  38. Russo J, Russo I . Biological and molecular bases of mammary carcinogenesis . Lab Invest . 57 . 2 . 112–37 . 1987 . 3302534.
  39. Web site: Reproductive Breast Cancer Risks Brochure . 20 October 2007 . https://web.archive.org/web/20071015071320/http://bcpinstitute.org/reproductive.htm#R2 . 15 October 2007 . dead.
  40. Alvarado MV, Alvarado NE, Russo J, Russo IH . Human chorionic gonadotropin inhibits proliferation and induces expression of inhibin in human breast epithelial cells in vitro . In Vitro Cell. Dev. Biol. Anim. . 30A . 1 . 4–8 . 1994 . 8193772 . 10.1007/BF02631407. 12638074 .
  41. Russo IH, Koszalka M, Russo J . Effect of human chorionic gonadotropin on mammary gland differentiation and carcinogenesis . Carcinogenesis . 11 . 10 . 1849–55 . 1990 . 2119909 . 10.1093/carcin/11.10.1849.
  42. Bernstein L, Hanisch R, Sullivan-Halley J, Ross RK . Treatment with human chorionic gonadotropin and risk of breast cancer . Cancer Epidemiol. Biomarkers Prev. . 4 . 5 . 437–40 . 1995 . 7549796 .
  43. B MacMahon . P Cole . J Brown . Etiology of human breast cancer: a review . J. Natl. Cancer Inst. . 50 . 21–42 . 1973 . 4571238 . 21–42. 10.1093/jnci/50.1.21 .
  44. Frazier. A Lindsay. Ryan. Catherine Tomeo. Rockett. Helaine. Willett. Walter C. Colditz. Graham A. Adolescent diet and risk of breast cancer. Breast Cancer Research. February 2003. 5. 3. R59-64. 10.1186/bcr583. 164999. 12631400 . free .
  45. Jasen . Patricia . 1 October 2005. Breast Cancer and the Politics of Abortion in the United States . Medical History . 49 . 4 . 423–444 . Their study supported the theory that structural changes in breast tissue are responsible for the lasting, protective effect of full-term pregnancy. They observed that abortion left the rats highly susceptible to developing cancer, but that the aborted rats "were at the same risk as virgin animals treated with the carcinogen" (italics mine). Over the next two decades, however, their findings would be cited repeatedly as evidence that pregnancy begins a process of breast change which, when stopped by abortion, put female rats (and thus humans) at greater risk of cancer than those who had never been pregnant. . 16562329 . 1251638 . 10.1017/S0025727300009145.
  46. Web site: Yeoman . Barry . Scientist Who Hated Abortion . 1 February 2003 . Michael Lewis . 9 September 2014 . Discover . 30 October 2019 . https://web.archive.org/web/20191030034812/http://discovermagazine.com/2003/feb/feathated . live .
  47. Web site: Abortion and Breast Cancer Risk . American Cancer Society . 8 May 2017 . Cohort studies and studies that used records to determine the history of abortions have not found an increased risk...Researchers generally consider the conclusions from cohort studies to be stronger than those from case-control studies. . 9 August 2021 . https://web.archive.org/web/20210809214325/https://www.cancer.org/cancer/cancer-causes/medical-treatments/abortion-and-breast-cancer-risk.html . live .
  48. Bartholomew. LL. Grimes. DA. The alleged association between induced abortion and risk of breast cancer: biology or bias?. Obstetrical & Gynecological Survey. November 1998. 53. 11. 708–14. 9812330. Two recent, large cohort studies, which are less susceptible to bias, showed either protection or no effect on breast cancer risk from an induced abortion.. 10.1097/00006254-199811000-00024.
  49. Grimes. David A.. Induced Abortion: An Overview for Internists. Annals of Internal Medicine. 20 April 2004. 140. 8. 620–6. 10.7326/0003-4819-140-8-200404200-00009. 15096333. 11334454 .
  50. Brind. J. Chinchilli. VM. Severs. WB. Summy-Long. J. Induced abortion as an independent risk factor for breast cancer: a comprehensive review and meta-analysis.. Journal of Epidemiology and Community Health. October 1996. 50. 5. 481–96. 8944853. 10.1136/jech.50.5.481. 1060338.
  51. Blettner. M. Chang-Claude. J. Scheuchenpflug. T. Induced abortion as an independent risk factor for breast cancer.. Journal of Epidemiology and Community Health. August 1997. 51. 4. 465–7. 9328561. 10.1136/jech.51.4.465. 1060523.
  52. Davidson. T. Abortion and breast cancer: a hard decision made harder.. The Lancet Oncology. December 2001. 2. 12. 756–8. 10.1016/S1470-2045(01)00591-5. 11902518.
  53. Wingo. PA. Newsome. K. Marks. JS. Calle. EE. Parker. SL. The risk of breast cancer following spontaneous or induced abortion.. Cancer Causes & Control. January 1997. 8. 1. 93–108. 10.1023/a:1018443507512. 9051328. 7002516.
  54. Beral. V. Bull. D. Doll. R. Peto. R. Reeves. G. Collaborative Group on Hormonal Factors in Breast. Cancer.. Breast cancer and abortion: collaborative reanalysis of data from 53 epidemiological studies, including 83?000 women with breast cancer from 16 countries.. Lancet. 27 March 2004. 363. 9414. 1007–16. 15051280. 10.1016/s0140-6736(04)15835-2. 20751083.
  55. Guo. J. Huang. Y. Yang. L. Xie. Z. Song. S. Yin. J. Kuang. L. Qin. W. Association between abortion and breast cancer: an updated systematic review and meta-analysis based on prospective studies.. Cancer Causes & Control. June 2015. 26. 6. 811–9. 25779378. 10.1007/s10552-015-0536-1. 1492061.
  56. Web site: Facts on Induced Abortion in the United States . 4 November 2007 . guttmacher.org . https://web.archive.org/web/20071013034110/http://www.guttmacher.org/pubs/fb_induced_abortion.html . 13 October 2007 . dead .
  57. Cannold. Leslie. Understanding and Responding to Anti-Choice Women-Centred Strategies. Reproductive Health Matters. 10. 19. 2002. 171 - 179. 12369322. 10.1016/s0968-8080(02)00011-3. 11062709. https://web.archive.org/web/20131004215635/http://cannold.com/static/files/assets/9483d047/RHMarticle.pdf. 4 October 2013. dead.
  58. Web site: The Last Abortion Clinic . 4 November 2007 . PBS.org. https://web.archive.org/web/20071023054735/http://www.pbs.org/wgbh/pages/frontline/clinic/. 23 October 2007 . live.
  59. News: Group angered by billboards linking breast cancer to abortion . 4 November 2007 . CBC . Canada . 25 October 2005. https://web.archive.org/web/20071218174324/http://www.cbc.ca/health/story/2005/10/25/pink-ribbon051025.html. 18 December 2007 . live.
  60. Beral V, Bull D, Doll R, Peto R, Reeves G . Breast cancer and abortion: collaborative reanalysis of data from 53 epidemiological studies, including 83 000 women with breast cancer from 16 countries . Lancet . 363 . 9414 . 1007–16 . 2004 . 15051280 . 10.1016/S0140-6736(04)15835-2. 20751083 .
  61. Web site: Vote for the Golden Boob! . 4 November 2007 . goldenboob.org . https://web.archive.org/web/20071020054209/http://www.goldenboob.org/ . 20 October 2007 . dead.
  62. Web site: Elster . Naomi . It's time to talk about the pseudoscience corrupting the abortion debate . The Guardian . 19 December 2019 . 29 September 2017 . Despite the broadening and widening of the pro-choice movement, there remains a near-total ban on abortion and an aggravating amount of pseudoscience in the air. When researchers from Johns Hopkins University examined a large number of studies on abortion and mental health, the ones carried out to the highest standards revealed that there were very few, if any, negative mental health consequences of having an abortion. ... Despite this, we are constantly hearing that abortions lead to mental health problems. Twice in the past week, we have also encountered the insidious myth that abortion causes breast cancer because of the resultant hormone changes. .
  63. Web site: Naomi Elster . 2019-12-19 . Naomi Elster is a writer and a scientist. She has a PhD in breast cancer. Her nonfiction covers science, health, and an evidence-based approach to women’s issues. . 20 December 2019 . https://web.archive.org/web/20191220052422/https://daily.jstor.org/daily-author/naomi-elster/ . live .
  64. Web site: Physicians For Life – Abstinence, Abortion, Birth Control – Need to Inform Patients of Abortion – Breast Cancer Link . 4 November 2007 . physiciansforlife.org . https://web.archive.org/web/20070927232722/http://www.physiciansforlife.org/content/view/105/26/ . 27 September 2007 . dead.
  65. Web site: Counseling and Waiting Periods for Abortion . 2019-12-01 . 2019-12-22 . . 21 June 2021 . https://web.archive.org/web/20210621074425/https://www.guttmacher.org/state-policy/explore/counseling-and-waiting-periods-abortion . live .
  66. News: Questions on states' abortion warnings . 4 November 2007 . The Boston Globe . 10 November 2004 . Laura . Meckler . 24 September 2015 . https://web.archive.org/web/20150924152327/http://www.boston.com/news/nation/articles/2004/11/10/questions_on_states_abortion_warnings/?rss_id=Boston%20Globe%20--%20National%20News . live .
  67. Chavkin W . Topics for our times: public health on the line—abortion and beyond . American Journal of Public Health . 86 . 9 . 1204–6 . 1996 . 8806368 . 10.2105/AJPH.86.9.1204 . 1380579.
  68. News: Appel. Jacob M. Abortion: A Healthy Choice. 10 September 2014. The Huffington Post. 25 September 2016. https://web.archive.org/web/20160925225005/http://www.huffingtonpost.com/jacob-m-appel/abortion-a-healthy-choice_b_316825.html. live.
  69. http://www.upi.com/Top_News/US/2017/05/01/Trump-taps-anti-abortion-leader-Charmaine-Yoest-for-HHS-post/8081493639309/ Trump taps anti-abortion leader Charmaine Yoest for HHS post
  70. News: Abortion and Breast Cancer . 9 September 2014 . The New York Times . 2003-01-03 . 7 October 2020 . https://web.archive.org/web/20201007122339/https://www.nytimes.com/2003/01/06/opinion/abortion-and-breast-cancer.html . live .
  71. Web site: Breast Cancer Prevention Institute . 4 November 2007 . bcpinstitute.org . https://web.archive.org/web/20071015194003/http://bcpinstitute.org/nci_minority_rpt.htm . 15 October 2007 . dead.
  72. Web site: Abortion Clinic of Fargo . 4 November 2007 . redriverwomensclinic.com. https://web.archive.org/web/20071009114033/http://www.redriverwomensclinic.com/. 9 October 2007 . live.
  73. Web site: ARCHIVE| March 28, 2002 – Judge Rejects Abortion-Breast Cancer Scare Tactic . 4 November 2007 . crlp.org . https://web.archive.org/web/20061130074932/http://www.crlp.org/pr_02_0328ND.html . 30 November 2006 . dead.
  74. Web site: Controversy over alleged breast cancer link lands abortion clinic in court . 4 November 2007 . womenspress.com . https://web.archive.org/web/20110717015204/http://www.womenspress.com/main.asp?Search=1&ArticleID=1580&SectionID=1&SubSectionID=1&S=1 . 17 July 2011 . dead.
  75. Web site: John A. Kindley Law Office: The ABC Link . 7 November 2007 . John Kindley . 19 June 2019 . https://web.archive.org/web/20190619130213/http://www.kindleylaw.com/?page_id=10 . live .
  76. Web site: Amy Jo Kjolsrud v. MKB Management Corporation . 4 November 2007 . 10 July 2012 . https://archive.today/20120710192005/http://caselaw.lp.findlaw.com/scripts/getcase.pl?court=nd&vol=20030023&invol=1 . live .

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