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Abortion and mental health: quantitative synthesis and analysis of research published 1995–2009

  • Priscilla K. Coleman (a1)

Given the methodological limitations of recently published qualitative reviews of abortion and mental health, a quantitative synthesis was deemed necessary to represent more accurately the published literature and to provide clarity to clinicians.


To measure the association between abortion and indicators of adverse mental health, with subgroup effects calculated based on comparison groups (no abortion, unintended pregnancy delivered, pregnancy delivered) and particular outcomes. A secondary objective was to calculate population-attributable risk (PAR) statistics for each outcome.


After the application of methodologically based selection criteria and extraction rules to minimise bias, the sample comprised 22 studies, 36 measures of effect and 877 181 participants (163 831 experienced an abortion). Random effects pooled odds ratios were computed using adjusted odds ratios from the original studies and PAR statistics were derived from the pooled odds ratios.


Women who had undergone an abortion experienced an 81% increased risk of mental health problems, and nearly 10% of the incidence of mental health problems was shown to be attributable to abortion. The strongest subgroup estimates of increased risk occurred when abortion was compared with term pregnancy and when the outcomes pertained to substance use and suicidal behaviour.


This review offers the largest quantitative estimate of mental health risks associated with abortion available in the world literature. Calling into question the conclusions from traditional reviews, the results revealed a moderate to highly increased risk of mental health problems after abortion. Consistent with the tenets of evidence-based medicine, this information should inform the delivery of abortion services.

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2 Coleman, PK. Induced abortion and increased risk of substance use: a review of the evidence. Curr Women's Health Rev 2005; 1: 2134.
3 Coleman, PK, Reardon, DC, Strahan, TS, Cougle, JR. The psychology of abortion: a review and suggestions for future research. Psychol Health 2005; 20: 237–71.
4 Thorp, J, Hartman, K, Shadigan, E. Long-term physical and psychological health consequences of induced abortion: review of the evidence. Obstet Gynecol Surv 2003; 58: 6779.
5 American Psychological Association Task Force on Mental Health and Abortion. Report of the American Psychological Association Task Force on Mental Health and Abortion. APA, 2008.
6 Charles, VE, Polis, CB, Sridhara, SK, Blum, RW. Abortion and long-term mental health outcomes: a systematic review of the evidence. Contraception 2008;78: 436–50.
7 Robinson, GE, Stotland, NL, Russo, NF, Lang, JA, Occhiogrosso, M. Is there an ‘abortion trauma syndrome’? Critiquing the evidence. Harv Rev Psychiatry 2009; 17: 268–90.
8 Kost, K, Forrest, JD. Intention status of US births in 1988: differences by mothers' socioeconomic and demographic characteristics. Fam Plann Perspect 1995; 27: 11–7.
9 Squires, S. Most pregnancies unplanned or unwanted, study says. Washington Post 9 May 1995; 11: 7.
10 Coleman, PK. Resolution of unwanted pregnancy during adolescence through abortion versus childbirth: individual and family predictors and consequences. J Youth Adolesc 2006; 35: 903–11.
11 Henshaw, R, Naji, S, Russell, I, Templeton, A. Psychological responses following medical abortion (using mifepristone and gemeprost) and surgical vacuum aspiration: a patient-centered, partially randomized prospective study. Acta Obstet Gynec Scand 1994; 73: 812–8.
12 Lauzon, P, Roger-Achim, D, Achim, A, Boyer, R. Emotional distress among couples involved in first trimester abortions. Can Fam Physician 2000; 46: 2033–40.
13 Lyndon, J, Dunkel-Schetter, C, Cohan, CL, Pierce, T. Pregnancy decision making as a significant life event: a commitment approach. J Pers Soc Psychol 1996; 71: 141–51.
14 Major, B, Cozzarelli, C, Cooper, ML, Zubek, J, Richards, C, Wilhite, M, et al. Psychological responses of women after first trimester abortion. Arch Gen Psychiatry 2000; 57: 777–84.
15 Major, B, Cozzarelli, C, Sciacchitano, AM, Cooper, ML, Testa, M, Mueller, PM. Perceived social support, self-efficacy, and adjustment to abortion. J Pers Soc Psychol 1990; 59: 186–97.
16 Miller, WB. An empirical study of the psychological antecedents and consequences of induced abortion. J Soc Issues 1992; 48: 6793.
17 Miller, WB, Pasta, DJ, Dean, CL. Testing a model of the psychological consequences of abortion. In The New Civil War: The Psychology, Culture, and Politics of Abortion (eds Beckman, LJ, Harvey, SM): pp. 235–67. American Psychological Association, 1998.
18 Reardon, DC, Coleman, PK. Relative treatment rates for sleep disorders following abortion and childbirth: a prospective record-based study. Sleep 2006; 29: 105–6.
19 Slade, P, Heke, S, Fletcher, J, Stewart, PA. Comparison of medical and surgical methods of termination of pregnancy: choice, psychological consequences, and satisfaction with care. Br J Obstet Gynaecol 1998; 105: 1288–95.
20 Coleman, PK, Coyle, CT, Shuping, M, Rue, VM. Induced abortion and anxiety, mood, and substance abuse disorders: isolating the effects of abortion in the National Comorbidity Survey. J Psychiatr Res 2009; 43: 770–6.
21 Dingle, K, Alati, R, Clavarino, A, Najman, JM, Williams, GM. Pregnancy loss and psychiatric disorders in young women: an Australian birth cohort study. Br J Psychiatry 2008; 193: 455–60.
22 Fergusson, DM, Horwood, LJ, Boden, JM. Abortion and mental health disorders: evidence from a 30-year longitudinal study. Br J Psychiatry 2008; 193: 444–51.
23 Fergusson, DM, Horwood, LJ, Ridder, EM. Abortion in young women and subsequent mental health. J Child Psychol Psychiatry 2006; 47: 1624.
24 Pedersen, W. Childbirth, abortion and subsequent substance use in young women: a population-based longitudinal study. Addiction 2007; 102: 1971–8.
25 Lipsey, MW. Identifying interesting variables and analysis opportunities. In The Handbook of Research Synthesis and Meta-Analysis, 2nd edn (eds Cooper, H, Hedges, LV, Valentine, JC): 147–58. Russell Sage Foundation, 2009.
26 Coleman, PK, Reardon, DC, Cougle, J. Substance use among pregnant women in the context of previous reproductive loss and desire for current pregnancy. Br J Health Psychol 2005; 10: 255–68.
27 Steinberg, JR, Russo, NF. Abortion and anxiety: what's the relationship? Soc Sci Med 2008; 67: 238–52.
28 Coleman, PK, Maxey, DC, Spence, M, Nixon, C. The choice to abort among mothers living under ecologically deprived conditions: predictors and consequences. Int J Ment Health Addiction 2009; 7: 405–22.
29 Coleman, PK, Reardon, DC, Rue, V, Cougle, J. History of induced abortion in relation to substance use during subsequent pregnancies carried to term. Am J Obstet Gynecol 2002; 187: 1673–8.
30 Coleman, PK, Reardon, DC, Rue, V, Cougle, J. State-funded abortions vs. deliveries: a comparison of outpatient mental health claims over four years. Am J Orthopsychiatry 2002; 72: 141–52.
31 Cougle, J, Reardon, DC, Coleman, PK. Depression associated with abortion and childbirth: a long-term analysis of the NLSY cohort. Med Sci Monit 2003; 9: CR105–12.
32 Cougle, J, Reardon, DC, Coleman, PK, Rue, VM. Generalized anxiety associated with unintended pregnancy: a cohort study of the 1995 National Survey of Family Growth. J Anxiety Disord 2005; 19: 137–42.
33 Gilchrist, AC, Hannaford, PC, Frank, P, Kay, CR. Termination of pregnancy and psychiatric morbidity. Br J Psychiatry 1995; 167: 243–8.
34 Gissler, M, Hemminki, E, Lonnqvist, J. Suicides after pregnancy in Finland, 1987–94: register linkage study. BMJ 1996; 313: 1431–4.
35 Pedersen, W. Abortion and depression: a population-based longitudinal study of young women. Scand J Public Health 2008; 36: 424–8.
36 Reardon, DC, Cougle, J. Depression and unintended pregnancy in the National Longitudinal Survey of Youth: a cohort study. BMJ 2002; 324: 151–2.
37 Reardon, DC, Cougle, J, Ney, PG, Scheuren, F, Coleman, PK, Strahan, TW. Deaths associated with delivery and abortion among California Medicaid patients: a record linkage study. South Med J 2002; 95: 834–41.
38 Reardon, DC, Cougle, J, Rue, VM, Shuping, M, Coleman, PK, Ney, PG. Psychiatric admissions of low-income women following abortion and childbirth. CMAJ 2003; 168: 1253–6.
39 Reardon, DC, Coleman, PK, Cougle, J. Substance use associated with prior history of abortion and unintended birth: a national cross sectional cohort study. Am J Drug Alcohol Abuse 2004; 26: 369–83.
40 Rees, DI, Sabia, JJ. The relationship between abortion and depression: new evidence from the Fragile Families and Child Wellbeing Study. Med Sci Monit 2007; 13: 430–6.
41 Schmiege, S, Russo, NF. Depression and unwanted first pregnancy: longitudinal cohort study. BMJ 2005; 331: 1303.
42 Taft, AJ, Watson, LF. Depression and termination of pregnancy (induced abortion) in a national cohort of young Australian women: the confounding effect of women's experience of violence. BMC Public Health 2008; 8: 75.
43 Borenstein, M, Hedges, LV, Higgins, JPT, Rothstein, HR. Introduction to Meta- Analysis. Wiley, 2009.
44 Appleby, L. Suicide during pregnancy and in the first postnatal year. BMJ 1991; 302: 137–40.
45 Kleiner, GJ, Greston, WM, (eds). Suicide in Pregnancy. John Wright, 1984.
46 Lindahl, V, Pearson, JL, Colpe, L. Prevalence of suicidality during pregnancy and the postpartum. Arch Womens Ment Health 2005; 8: 7787.
47 Schiff, MA, Grossman, DC. Adverse perinatal outcomes and risk of postpartum suicide attempt in Washington State, 1987–2001. Pediatrics 2006; 118: e66975.
48 Bailey, PE, Bruno, ZV, Bezerra, MF, Queiroz, J, Oliveira, CM, Chen-Mok, M. Adolescent pregnancy 1 year later: the effects of abortion vs. motherhood in Northeast Brazil. J Adolesc Health 2001; 29: 223–32.
49 Fergusson, DM, Boden, JM, Horwood, LJ. Abortion among young women and subsequent life outcomes. Perspect Sex Reprod Health 2007; 39: 612.
50 Fergusson, DM. Abortion and mental health. Psychiatr Bull 2008; 32: 321–4.
51 Mota, NP, Burnett, M, Sareen, J. Associations between abortion, mental disorders, and suicidal behaviour in a nationally representative sample. Can J Psychiatry 2010; 55: 239–47.
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Abortion and mental health: quantitative synthesis and analysis of research published 1995–2009

  • Priscilla K. Coleman (a1)
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Re:Abortion and mental health: quantitative synthesis and analysis of research published 1995-2009

Laura B. Page, High School Teacher
01 February 2012

I have followed with interest, both professional and personal, the commentary in this forum. The Coleman meta-analysis has been raked over the coals from multiple points of view, but I have yet to see any replication of the study with either concurrent or divergent results, nor any plans to attempt a similar study. On the contrary, most respondents have not been neutrally assessing the paper of a peer: they have angrily attacked a perceived threat.

My credentials, and thus my perspective, vary somewhat from most of those represented herein: I hold a B.A. in psychology, an M.B.A. in economics, and an M.Ed. in secondary education. I teach a variety of English, mathematics, and social science courses--including psychology--tohigh school and undergraduate students.

Working with young people daily, I inevitably learn their stories; pregnancy happens, and so does abortion. Many young women feel pressured into an abortion decision by boyfriend/husband, family, social, economic, or school circumstances. Add grief, guilt, and/or remorse to the mix, as well as the coping attempts (including risky behaviors) of the relatively immature, and the picture becomes increasingly complex. Granted, my evidence is purely anecdotal, but I have seen it: there is a connection between abortion and mental health, it needs to be studied further, and Coleman needs not to be the only one who researches it.

Those who have levied criticisms of Coleman's methodology might applytheir own criteria to her data, or gather their own data meeting her studycriteria, to prove or disprove her hypothesis. Others might start from scratch, formulate their own hypotheses, and proceed from there. Regardless, while I realize that the purpose of peer review is to open one's research to the criticism of other professionals, if all one does isto criticize, nothing has been achieved, and the goals of research have not been advanced. Worst of all, in this case, no women have been helped.

As to those concerned with bias, Coleman's follow-up comments are enlightening. Ultimately, valid results will emerge when multiple researchers, regardless of political persuasion, put their own biases aside, ask uncomfortable questions, and go where the data lead them.

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Conflict of interest: Page volunteers at a crisis pregnancy center, where she peer-counsels pregnant women and leads a support group for women who have had abortions in the past. Participation is voluntary and all services are offered free of charge. The center does not provide or refer for abortion services.

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Abortion, Mental Health and Charges of Guilt By Association

David C. Reardon, Director
17 January 2012

Coleman's meta-analysis of abortion and mental health studies was harshly criticized in three letters by five authors (Drs. Robinson, Stotland, Nadelson, Coyne, and Littell) who all cited an Ethics & Medicine(1) paper which I wrote (not Coleman) as evidence that Coleman cannot be trusted.

My full response(2) is summarized below:

Robinson's assertion that I am Coleman's "leader" is nonsense. We have no institutional, financial, or personal entanglements.

I gathered data that required the analysis of research psychologists. I am thankful that Coleman agreed to analyze it and help present it in a scientifically accurate and impartial manner.

As a biomedical ethicist, I explore the intersections of medicine, science, philosophy, theology, ethics, and the law. When writing papers intended for each of these fields, I seek to use the language and tools appropriate to each field.

The cited article was a response to a pro-life philosopher who argued that any evidence of emotional suffering of women following abortion is essentially irrelevant to the moral argument against abortion and counter productive to pro-life efforts.(3) The core of my response was that Christians have an obligation to "consistently demonstrate as much concern for women as for their unborn children," and that "our advocacy for women must be consistent and unconditional both for those who are facing crisis pregnancies and for those who have had abortions." I further argued that "the harm abortion does to women is just as real as that done to the human fetus."(1)

It also reflected my sincere belief that abortion involves substantial dangers to specific subgroups of women. Unfortunately critics have distorted this into the charge that I seek to scare women with exaggerated risks.(4) That is untrue. There are real risks, especially for certain higher risk groups.(5) Women should be told of the truth, with neither exaggeration nor dismissal and minimization.

Women who dare to express emotional trials following an abortion face rejection from people on both sides. A few pro-lifers harshly dismiss these women as "sinners" who deserve a lifetime of grief. Conversely, at least a few pro-choicers dismiss their grief as "whining," or "rare," or suggest that only women mentally unstable prior to their abortions would complain so much.(4)

By contrast, the post-abortion healing movement simply asks those on both sides to respect the experiences of women grieving a past abortion.

But even this pro-healing position is attacked. On one hand, pro-choicers accuse us of manipulating gullible women into falsely blaming unrelated life problems on their abortions.(4) Some pro-life advocates, meanwhile, accuse us of encouraging an unprincipled, narcissistic worldview that diminishes the moral absolutes regarding the sanctity of life.(3)

To my mind the question of whether abortion is the sole, direct cause of certain mental illnesses is far less important than the fact that many self-aware women believe it has contributed to their problems and are asking for understanding and help.(5) Why is it so hard to simply accept their self-assessments and stated needs? Women deserve better.


1. Reardon DC. A defense of the neglected rhetorical strategy (NRS) Ethics Med. 2002 Summer;18(2):23-32.

2. Reardon DC. Abortion and Mental Health Deniers' Attack and Distract Strategy. Oct. 22, 2011

3. Beckwith FJ. Taking abortion seriously: a philosophical critique of the new anti-abortion rhetorical shift. Ethics Med. 2001 Fall;17(3):155-66.

4. Baezlon E. Is There a Post-Abortion Syndrome? New York Times Magazine. January 21 2007

5. Burke T, Reardon DC. Forbidden Grief: The Unspoken Pain of Abortion. Springfield, Ill: Acorn Books; 2002.

CONFLICT OF INTEREST: I am the Director of the Elliot Institute
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Conflict of interest: None Declared

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The Correct Use of Ethics and Precaution with Regard to Abortion and Mental Health

Christian Munthe, Professor of Practical Philosophy
04 January 2012

The debate on Coleman's study has moved into ethics, as commentators claim it to support conclusions about the organisation of abortion services (AS). In her reply, Coleman sides with these voices. However, closer scrutiny puts these suggestion into question.

Koch argue that a "principle of precaution" (PP) supports the notion AS providing pre-counselling about possible risks to mental health,since PP says that merely possible risk may motivate preventive action. However, this holds for all risks, also those imposed by preventive actions. PP has to be allowed to thus "cut both ways" to avoid incoherenceand paradox [1, 2]. To appraise if some action, B, to prevent a possibly risky action, A, should be taken, also the outcomes of A and B, should there be no risk, needs consideration, as well as risks of B. If no causallink between abortion and mental helth exists, for AS to inform about a possible risk may scare away patients in spite of their reason to seek AS and may, moreover, impose risks on those choosing to have the procedure bydelaying it. Unbiased pre-counselling about the current scientific situation would not likely further patients' decision quality or avoid harm. It would have to work through the complexity of the current discussion, including the declared ideologic agenda of Coleman, bringing risks of confusing decision making and inducing harm. [3, 4]. Alternatively, quality-assured, manageable information offering a real chance of supporting decision making without inducing harm may be included. This expresses the idea of PP that potentially risky actions should be postponed waiting for clear evidence against too serious risks [2].

Puccetti argue that, regadless of Coleman's study, AS should include "in-depth analysis of the various factors known to interfere with the psychological outcomes" as a pre-procedure. The basis for this is thatabortion has not been shown to benefit mental health. No ethical principleis presented to back up this argument, but one may generalize the suggestion into one: If a health care practice has not been proven to be beneficial to mental health, it should not be allowed unless preceded by an in depth analysis of the various factors known to interfere with the psychological outcomes. This principle has far-reaching implications, since risk factors for mental health problems all across health care, while there is normally no proven mental health benefits. The principle also rules out the original suggestion: the suggested analysis should not be made before another analysis has been made and the same holds with respect to that additional analysis, and so on.

These proposals and Coleman's own response rest on the notion of the most important task being to discourage women from having abortions. If the ethical baseline is to be care for mental health, however, the proper conclusion should rather be about access to mental health care. If Colemanis wrong, anyone may be burdened by mental health problems independently of whetheher or not they contemplate abortion. If she is right, there should be a special readiness to attend to mental health needs in AS. If feasible, harmless pre-abortion identification of high-risk cases may be added to this. Neither Coleman nor her supporters have considered anythingin this vein and this adds to suspiscions of an undisclosed ideological conflicts of interest.

References1. Sandin P, Peterson M, Hansson SO, Rud?n C, Juthe A (2001). Five ChargesAgainst thePrecautionary Principle. Journal of Risk Research 5: 287-99.

2. Munthe C (2011). The Price of Precaution and the Ethics of Risk. Dordrecht, Heidelberg, London & New York: Springer, ch. 2.

3. Juth N (2005). Genetic Information: Values and Rights. Gothenburg:Acta Universitatis Gothoburgensis, ch. 3.

4. Juth N, Munthe C (2012). The Ethics of Screening in Health Care and Medicine. Dordrecht, Heidelberg, London & New York: Springer, ch. 4.

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Conflict of interest: CM has been conducting bioethics research and published blog-posts in the reproductive and related areas, often with results critical of typical so-called pro-life positions, but also arguing for regulation around medical and scientific practices.

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Re:Re: Abortion and Mental Health

Gregory L. Kinney, Epidemiologist
29 November 2011

An author should be commended for defending the work that they have done when that work is questioned by peers. Coleman however does not address a specific analytical observation made by authors that have commented (Coyne, Polis, Littel and Thygesen among others). Coleman included multiple analyses performed within multiple studies that represent the same study populations (Table 1, citation 10, 20, 21, 22, 24, 27, 29, 30, 32, 39 where each of these citations represents a study population being counted more than once in the meta-analysis). Doing so inappropriately increases the sample size and reduces the variance in the pooled measure. This causes the pooled estimate to be biased as the analytical technique was not applied in an appropriate manner and represents an inflated N. In her response the author addresses that observation by discussing random verses fixed effects and weighting but this is not the issue at hand;

"The random effects model yields an estimate of the mean of a distribution of true effects; whereas in the fixed effects model there is an assumption that all the included studies share one common effect. When assigning weights to studies in a fixed effects model, the smaller ones are afforded less importance, since the same effect is believed to be moreprecisely assessed in the larger studies. In contrast, in the random effects model, individual studies of varying sizes contribute data from distinct populations, all of which must be considered in the pooled estimate. Weighting is therefore more balanced in the random effects vs. fixed effects model with smaller studies given relatively more emphasis. In recognition of the heterogeneity, I not only employed the random effects model, but I ran separate meta-analyses based on distinct comparison groups and outcomes."

The author goes on to discuss her authorship of many of the included studies. This is done in the context of the existing literature and not the application of the specific analytical technique;

"Using the criteria outlined above, a significant proportion of the included studies (11/22) were articles that I authored or co- authored. However, having published 33 peer-reviewed articles, I believe I am more widely published on this topic than any other researcher in the world. It makes sense, therefore, that I am a co-author on a significant proportion of the included studies. Moreover, no studies satisfying the inclusion criteria were left out of the analyses."

Including ones own studies in a systematic review and meta-analysis is possible if done with care but that is, once again, not the issue at hand. The analytical issue is that the results of the meta-analyses reported in this study are incorrect because the meta-analysis was not performed in an appropriate manner and the independence assumption was violated. Authorship is not the issue; N is the issue.

Also Table 1 includes a citation inappropriately; Reardon & Cougle 2002 is cited as 35 which is actually Pederson 2008, Reardon & Cougle should be citation 36.

In light of the violation of a basic assumption of meta-analysis thispaper must be withdrawn. This violation biases the findings, their discussion and the conclusions and cannot be corrected in a response letter. This violation was pointed out by several other commenter's and the author failed to acknowledge and address it in her extensive response to comments.

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Conflict of interest: None declared

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Re: Abortion and Mental Health

Priscilla K. Coleman
17 November 2011

Dear Professor Tyrer:

I appreciate your decision to publish my meta-analysis on abortion and mental health in the British Journal of Psychiatry, despite the controversial results and critical commentary that has predictably followed. In the barrage of recent letters, the sentiments have varied widely and the many supportive arguments presented are worthy of additional comment; however, given space limitations, I have decided to focus on the criticisms to help ensure the results are given the attention deserved.

Before I address the most salient issues, I should note how encouraging it is to have a scholarly forum for discussing the many complexities inherent in conducting systematic reviews on this topic. The optimist in me is hopeful that this dialogue will foreshadow a new era wherein the research community is able to move beyond agendas and polarized discussions to focus exclusively on the well-being of women, the centre of this academic debate that is so frequently obscured.

There are some comments that I believe are without basis and may not have been made with a more careful, less emotional read of the article. For example, Littell and Coyne suggested scientific standards for systematic reviews were not followed. The protocol employed is detailed in the methodology section and the strategy was in line with recommendations in the Handbook of Research Synthesis and Meta-Analysis. Rather than focus on these types of comments, I address criticisms requiring more information from me to allow readers to make informed decisions regarding the merit of the issues raised. I specifically address heterogeneity, publication bias, selection criteria, and personal bias in the text that follows.

Heterogeneity: The studies included in the meta-analysis have a relatively high degree of heterogeneity given the demographic and cultural differences in sampling, the variability in control groups and outcomes, and differences in third variable controls, etc. Counter to the claim by Polis and colleagues, heterogeneity was addressed by employing a random effects model. The random effects model yields an estimate of the mean of a distribution of true effects; whereas in the fixed effects model there is an assumption that all the included studies share one common effect. When assigning weights to studies in a fixed effects model, the smaller ones are afforded less importance, since the same effect is believed to be more precisely assessed in the larger studies. In contrast, in the random effects model, individual studies of varying sizes contribute data from distinct populations, all of which must be considered in the pooled estimate. Weighting is therefore more balanced in the random effects vs. fixed effects model with smaller studies given relatively more emphasis.In recognition of the heterogeneity, I not only employed the random effects model, but I ran separate meta-analyses based on distinct comparison groups and outcomes.

Publication Bias: Goldacre and Lee provided a funnel plot analysis and presented it as evidence of publication bias. However, the funnel plot is largely inappropriate for heterogeneous meta-analyses, wherein studies are not likely from a single underlying population [1-4], and several investigatorshave warned that use of funnel plots with meta-analyses derived from heterogeneous samples may result in false-positive claims of publication bias [1-4]. When funnel plot asymmetry is detected in a heterogeneous meta-analysis, the cause is likely due to essential differences between the smaller and larger studies. For example, the majority of the smaller studies included in my meta-analysis employed substance use outcome variables and these outcomes tend to yield the strongest, most robust effects [5,6]. In addition, the larger studies were more likely than the smaller studies to include actual diagnoses for disorders, rarer events than cut off scores on single surveys. In the context of this meta-analysis, the funnel plot most certainly does not provide evidence of publication bias.

My experience attempting to locate unpublished data/studies on abortion and mental health has been very disheartening over the last 15 years,with virtually all requests ignored. I suspect reluctance to share unpublished data is an attempt to keep results that challenge contemporary views on abortion, indicating significant increased risks for adverse psychological effects,out of the public domain. In contrast, I believe energy is likely invested in seeing to it that non-significant findings, suggesting abortion carries no increased psychological risks, find their way into the journals. If there is any topic wherein many editors, researchers, and professional organizations are highly motivated to publish non-significant effects, it is this one, rendering publication bias less common than in other areas. Support for this notion can be found in the American Psychological Association's 42 year history of abortion advocacy.

In 1969 the APA passed a resolution which made the pro-choice political position the organization's official stance and declared abortion a civil right. For decades the APA has aligned itself with major organizations with pro-choice social agendas, including the American CivilLiberties Union Reproductive Freedom Project, National Abortion Federation, National Abortion Rights Action League, Guttmacher Institute, and Planned Parenthood among others, frequently submitting amicus briefs and providing congressional testimony. Martel[7] recently discussed the APA's position on abortion, among other issues,noting that the organization's stance has led them to promote psychological research and disseminate data to lawmakers to inform the public and advocate for societal change. Martel further pointed out that the political stance of theAPA lacks the strong backing of empirical data. With this long history of abortion advocacy by the strongest professional psychology organization in the world, politically motivated efforts to publish null findings to support and legitimize their position is logical.

Selection Criteria: As indicated under the methodology section of the meta-analysis, studies identified using the Medline and PsycINFO data bases were included based on sample size, comparison groups, outcome variables, controls for 3rd variables, use of odds ratios, and publication in English in peer-reviewed journals between 1995 and 2009. In an effort to isolate the effect of abortion on mental health, use of comparisons groups and controls for 3rd variables are basic methodological requirements consistent with the Bradford Hill criteria [8]. The majority of studies meeting these criteria and incorporated into the meta-analysis also had many other strong methodological features (multiple data points, nationally representative samples, etc.) I purposely avoided selecting from among the many more peripheral methodological criteria that could be argued as a necessary basis for including or excluding studies, when there is not universal agreement regarding strengths necessary to consider a study's results sufficiently reliable and valid, nor is there consensus on the particular deficiencies necessary for the wholesale dismissal of a study.

Using the criteria outlined above, a significant proportion of the included studies (11/22) were articles that I authored or co-authored. However, having published 33 peer-reviewed articles, I believe I am more widely published on this topic than any other researcher in the world. It makes sense, therefore, that I am a co-author on a significant proportion of the included studies. Moreover, no studies satisfying the inclusion criteria were left out of the analyses.

Curiously the issue of my not including a study by Danish researchers Munk-Olsen and colleagues published in the New England Journal of Medicine[9] was raised despite the fact that the paper came out long after my meta-analysis was completed and submitted for publication. Incidentally, the NEJM paper is presented as offering more reliable conclusions than the meta-analysis. However, there are several problematic features of this study. To begin with, Munk-Olsen and colleagues note that previous studies lack controls for third variables, but the only third variables they consider are age and parity. There are no controls for pregnancy intendedness, pressure to abort, marital status, income, education, exposure to violence and other traumas, etc. Many studies have been deemed inadequate based on only one of these variables not being accounted for (see APA Task Force Report [10]). The data indicated that rates of mental health problems were higher after abortion compared to childbirth (15.2% vs. 6.7%); however, the generally comparable rates before and after abortion were used to negate a possible causal link between abortion and mental health. This reasoning is problematic as many women were likely disturbed to the point of seeking help precisely because they were pregnant and contemplating an abortion or they were involved in troubled relationships. These factors may have resolved, yet disturbance rates remained elevated due to the impact of the abortion. Further, the Danish Civil Registration System contains over 40 years of data, but the researchers curiously compressed the study period to 12 years. A more appropriate strategy would have been to include all women experiencing an abortion, a birth, or no pregnancy and then compare pre and post-pregnancy mental health visits with statistical controls for all psychiatric visits pre-dating conception and all other relevant third variables described above.

Personal Bias: A quote from a presentation I gave at the annual meeting of the American Association of Prolife Obstetricians and Gynecologists was used by Goldacre and Lee to label me an "anti-abortion campaigner." This out of context comment was part of a broader call for more concerted efforts to create environments wherein objective scientists are able to make the psychology of abortion a priority. Once strong synopses of the best evidence are published, the data can and should be used to intelligibly inform policy. I am opposed to professional organizations like the APA creating a culture wherein it is perfectly acceptable for any political position (in this case pro-choice) to drive data collection efforts, restrict grants to researchers committed to a political agenda, serve as journal gatekeepers to block publication of findings that are not consonant with the political agenda, and ultimately use the biased information assembled to back policy.

I do not hold membership in any political organizations and my work has never been funded by any pro-life group. My expertise tends to be called upon by the pro-life community and unfortunately I am never asked to present my research or perspective on the literature to groups committed to a pro-choice political position. As a professor at a public university, what motivates me is simply the desire to foster high quality research and reach as many people as one individual can with an accurate appraisal of the literature, given the biases that permeate the study of abortion and dissemination of information through the usual channels. I do not have many graduate students working with me or large grants, and it is alarming that a researcher with such modest resources was the first to conduct a major quantitative review.

Rather than hurling unfounded accusations of personal bias, we need to more effectively utilize the well-established methods of science to fairly scrutinize the methodologies of individual studies, expand the empirical investigation of abortion and mental health, and develop a consensus-based standardized set of criteria for ranking studies meriting inclusion in reviews. Without agreement, the selected standards may be used to manipulate conclusions. For example, the ranking system employed by Charles et al. [11] ignored two central methodological considerations in prospective research designs: 1) percentage consenting toparticipate (no information was provided by the authors of the Gilchrist et al. [12] study that this team ranked as "Very Good"); and 2) retention of subjects over time. In the Gilchrist et al. study, only 34.4% of the termination group and 43.4% of the group that did not request termination were retained. A major problem with nearly all the recently published narrative reviews was somewhat arbitrary exclusion criteria at best and the purposeful selection of specific criteria resulting in dismissal of large bodies of evidence with politically incorrect results at worst.

By raising concerns of publication bias and attempting to undermine the credibility of an individual researcher, who managed to publish in a high profile journal, several people have sought to shift attention from the truly shameful and systemic bias that permeates the psychology of abortion. Professional organizations in the U.S. and elsewhere have arrogantly sought to distort the scientific literature and paternalistically deny women the information they deserve to make fully informed health care choices and receive necessary mental health counseling when and if an abortion decision proves detrimental.

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5.Coleman PK. Induced Abortion and increased risk of substance use: A review of the evidence. Current Women's Health Reviews 2005; 1: 21-34.

6.Mota NP, Burnett M, &Sareen J. Associations between abortion, mental disorders, and suicidal behaviour in a nationally representative sample. Can J Psychiatry 2010; 55(4):2 39-47.

7.Martel MM. The ethics of psychology's role in politics and the development and institution of social policy. Ethics & Behavior 2009; 19(2):103-111.

8.Hill BA. The environment and disease: Association or causation?Proceedings of the Royal Society of Medicine 1965; 58:295-300.

9.Munk-Olsen, T., et al., Induced first-trimester abortion and risk of mental disorder. N Engl J Med 2011; 364:332-9.

10.American Psychological Association Task Force on Mental Health and Abortion. Report of the American Psychological Association Task Force on Mental Health and Abortion 2008, Washington, DC: American Psychological Association.

11.Charles VE, Polis CB, Sridhara SK, Blum RW. Abortion and long-term mental health outcomes: a systematic review of the evidence. Contraception 2008;78:436-50.

12.Gilchrist A, Hannaford P, Frank P, Kay C. Termination of pregnancy and psychiatric morbidity. Br J Psychiatry 1995; 167:243-248.

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Conflict of interest: None declared

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