“Abortion does not harm mental health” is the headline in The Times , following a recent US report of psychiatric problems that occur after abortions. The newspaper suggests that the report’s findings will hinder the latest efforts of a group of anti-abortion MPs to “make it harder for British women to obtain terminations”. These MPs have tabled an amendment to the Human Fertilisation and Embryology Bill that would require all women to be counselled about psychiatric risks before they can be cleared to have a termination. This bill is to be debated by the House of Commons in October.
The systematic review excluded unreliable research and found no “credible” evidence that single abortions directly cause more mental health problems among adults with unwanted pregnancies than in those who deliver that pregnancy. They found one well-conducted study which provided reliable evidence that there was no difference between these groups for these outcomes. The evidence regarding multiple abortions was less certain, and the interpretation of the research is complicated by the fact that the studies often did not distinguish between abortions of wanted pregnancies (e.g. detected foetal abnormalities) and unwanted pregnancies, or consider factors such as poverty and drug use that raise the likelihood both of having an abortion and suffering mental illness.
Where did the story come from?
Dr Brenda Major was chairperson of the American Psychological Association (APA) ‘Task Force on Mental Health and Abortion’, which produced this report. The task force was established in 2006 to update a previous 1989 report on the topic, and is one of several task forces set up by the APA, an association of 148,000 psychologists based in Washington, DC. The report was published online on the APA website.
What kind of scientific study was this?
This was a systematic review of 50 English-language research studies published in peer-reviewed journals after 1989, which looked at the mental health of women who had an induced abortion, and the mental health of comparison groups of women. The review also looked at 23 studies which examined factors that may predict mental health among women who have had an elective abortion in the US.
In the report, the researchers outline the scope of their work and the background context to the establishment of the task force. They concentrate on the fact that since the 1989 report, four studies have supported its main conclusion, whereas four others have challenged it; reviewers of the newer literature have reached different conclusions. The 1989 APA report concluded that “severe negative reactions after legal, non-restrictive, first-trimester (early) abortion are rare and can best be understood in the framework of coping with a normal life stress” and that although some individual women experience severe distress or psychopathology following abortion, it was not clear that these symptoms are causally linked to the abortion.
The researchers begin this update by specifying the questions that their review of the research literature will address. Next, they discuss the conceptual frameworks important for understanding the literature on abortion and mental health. They also discuss the methodological issues worth considering when evaluating this literature in relation to the major question, “how does the mental health of women who have had an elective abortion compare with the mental health of various comparison groups?”
The researchers limited their search to studies that examined the implications of induced abortion for mental health outcomes. They also restricted the studies to those that used empirical research with a comparison group, and were published in English after 1989 in peer-reviewed journals. They reviewed other studies outside of this selected group to gain insight into the different experiences of abortion as reported by American women. After careful appraisal, 50 papers were identified as suitable for inclusion. Of these, 25 were a secondary analysis of public data sets or records originally collected for other purposes, and 18 of these were US-based studies. The researchers reviewed each study and its strengths and weaknesses in detail in order to reach a narrative conclusion.
What were the results of the study?
The task force identified 50 papers published in peer-reviewed journals between 1990 and 2007, which had analysed empirical data on the psychological experiences associated with induced abortion, compared with an alternative. Ten papers were based on a secondary analysis of two medical record data sets, and 15 papers were based on further analysis of another nine public data sets. There were 19 papers based on 17 studies that compared women who had an abortion in the first third of pregnancy (or where the timing was unspecified) with a comparison group. There were six studies of abortion for foetal abnormality.
The researchers concentrate on one 1995 study conducted in the UK, which they assess as having used rigorous methods. This is referred to as high-quality evidence. In the view of the task force, this provides the best scientific evidence yet that the chance of mental health problems among adult women who have an unplanned pregnancy is no greater if they have an elective first-trimester abortion than if they deliver that pregnancy.
What interpretations did the researchers draw from these results?
The researchers say that the best, published scientific evidence indicates that among adult women who have an unplanned pregnancy, the chance of mental health problems is no greater if they have a single elective first-trimester abortion or deliver that pregnancy.
Furthermore, the researchers say that the evidence regarding mental health risks associated with multiple abortions is more uncertain. Some studies show that women do experience sadness, grief and feelings of loss following an abortion, and some may experience "clinically significant disorders, including depression and anxiety". However, the task force found "no evidence sufficient to support the claim that an observed association between abortion history and mental health was caused by the abortion per se, as opposed to other factors".
What does the NHS Knowledge Service make of this study?
The researchers noted several limitations to the overall research underpinning this report:
- A failure to control for risk factors such as poverty, prior exposure to violence, a history of emotional problems, drug or alcohol use, or prior unwanted births may have led to some studies reporting associations between abortion history and mental health problems that are misleading. This occurs because these events can predispose women to experience both unwanted pregnancies and mental health problems after a pregnancy, irrespective of how the pregnancy is resolved, and therefore can lead to an apparent link between mental health problems and abortion when none exists.
- The fact that women have abortions for many different reasons (and within different personal, social, economic and cultural circumstances) can affect a woman's mental state following abortion.
- The underreporting of abortions in the surveys may have introduced potential bias. It is unclear whether this bias would be toward overestimating or underestimating the adverse impact of abortion.
- Another potentially serious methodological problem encountered was the loss of cases during the follow-up for a study. This attrition, the researchers say, has been a long-standing concern in studies of abortion, and few of the studies they found tested or reported the reasons for it.
The task force noted that despite the importance of understanding the mental health implications of abortion compared to its alternatives – motherhood or adoption – very few studies included appropriate comparison groups for addressing this issue. Following on from this, the task force calls for better-designed, rigorously conducted research on the topic to "help disentangle confounding factors and establish relative risks of abortion compared to its alternatives".
Sir Muir Gray adds...
Good evidence for policy making.
Analysis by Bazian
Edited by NHS Website
Links to the headlines
The Times, 18 August 2008
The Daily Telegraph, 18 August 2008
Links to the science
American Psychological Association, August 12 2008
Cochrane Database Syst Rev 2002, Issue 4