Not all studies on the mental
health impact of abortion are created equal. Antiabortion activists
often attempt to capitalize on the fact that the public and many policymakers
cannot distinguish between well-conducted studies and those that fall
in the "junk science" category. Fortunately, two respected teams
of researchers recently conducted separate reviews of the scientific
literature on abortion and mental health. In short: Based on the best
scientific evidence available, there is no credible evidence that abortion,
in and of itself, causes mental health problems for most women.  

In fact, according to the review by
American Psychological Association (APA),
methodological flaws are "pervasive in the literature on abortion
and mental health," and "the best scientific evidence indicates
that the relative risk 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 did deliver the pregnancy." 

Another comprehensive review
of the scientific literature, by researchers
at Johns Hopkins University,
likewise found that "the highest-quality research available does not
support the hypothesis that abortion leads to long-term mental health
problems. Lingering post-abortion feelings of sadness, guilt, regret,
and depression appear to occur in only a minority of women." The Johns
Hopkins review also found a "clear trend" by which "the highest
quality studies had findings that were mostly neutral" in terms of
mental health outcomes for women obtaining abortions. By contrast, they
found that studies with the most flawed methodologies consistently found
negative mental health outcomes to be associated with abortion.  

Assessing the evidence  

The APA identified a number
of major flaws in the literature on abortion and mental health: failing
to compare mental health outcomes between women who have abortion and
women who have unintended pregnancies, failing to take into account
preexisting mental health conditions (that could account for both abortion
and later mental health problems), using samples that were too small
or too restricted to allow for generalizations to the larger population
of women, failing to account for the fact that many women do not report
abortions, and using faulty measurement of mental health outcomes.  

Take, for example, a recent
study authored by Priscilla Coleman and her colleagues, published in
the Journal of Psychiatric Research. The authors use data from
a nationally representative sample of women aged 15-54 years old in
1990-1992. After taking into account 21 background characteristics of
respondents, they assert that abortion is associated with 12 of the
15 mental health outcomes examined in their analysis. But several fundamental
flaws detract from the validity of their findings. Previous research
has established that only about half of abortions are reported on nationally
representative surveys, a shortcoming for which Coleman fails to correct.
If half of women who have abortions aren’t reporting them, then researchers
cannot determine if those abortions are, or are not, associated with
subsequent mental health outcomes. The authors are also unable to adequately
control for potentially pre-existing mental health problems. For example,
women who have bipolar disorder may be more likely to have an unintended
pregnancy and subsequent abortion than women who do not have bipolar
disorder. The authors’ inability to control for these types of pre-existing
mental health condition leads them to assert that abortion leads to
bipolar disorder – an unlikely causal chain given that genetic factors
are a major contributor to this particular disorder.  

Even studies with better research
designs still have their limitations. For instance, two studies from
New Zealand suggest that abortion may be associated with, or cause,
later mental health problems. These studies employed a more rigorous
methodology than many prior studies addressing the issue. The principal
methodological strength of both studies, which were conducted by David
Fergusson and colleagues, is that they followed the same groups of women
over an extended period of time. Nonetheless, the APA review of the
2006 study cautions that "several design features limit conclusions
that can be drawn from this study," among them failing to control
for the wantedness or intentionality of pregnancy, not separating women
who had multiple abortions from those who had only one, and not accounting
for the underreporting of abortion.  

A more recent Fergusson
study (published in 2008) likewise did not separate women who had multiple
abortions from those who had only one, and it did not account for underreporting
of abortion. Another problem lies in its inadequate comparison groups.
Women unable to obtain abortions go on to have unintended, or even unwanted
births, and this outcome may also have negative mental health outcomes.
The challenge, therefore, is to compare mental health outcomes between
these women and women who have abortions. The manner in which Fergusson
and his colleagues attempted to address this in their most recent study
was inadequate. Instead of directly comparing these two groups of women,
the authors compared women who had abortions to all those who had not
and women who had unintended births to all those who had not.  

The research design of one
study is judged by experts, including at the APA, as close to ideal.
The study was conducted in the United Kingdom by the Royal College of
General Practitioners and the Royal College of Obstetricians and Gynecologists.
According to the APA, this study of 13,000 women in England and Wales
"stood out from the rest in terms of its methodological rigor."
It was based on a large, representative sample; used established diagnostic
categories to measure post-pregnancy/post-abortion mental health; controlled
for mental health and other factors that may have existed prior to the
pregnancy; and had appropriate comparison groups. The study, according
to the APA "provides high-quality evidence that among women faced
with an unplanned pregnancy, the relative risks of psychiatric disorder
among women who terminate the pregnancy are no greater than the risks
among women who pursue alternative courses of action."  

The bottom line is this: A
woman’s mental health before she faces an unwanted pregnancy is the
best indicator as to her likely mental health after an abortion. As
the APA report says, "Across studies, prior mental health emerged
as the strongest predictor of postabortion mental health."

That said, however, it is important
to acknowledge that for some small group of women, abortion may be directly
associated with negative mental health outcomes. These may, in fact,
be due to a number of factors that are difficult to separate from the
abortion per se, including perceived stigma, difficult life circumstances
surrounding the pregnancy, or the termination of an intended pregnancy
for health reasons. For purposes of screening and counseling, research
that seeks to determine which women may be most vulnerable to these
types of outcomes would be useful. At the same time, as both the APA
and Johns Hopkins reviews note, women typically experience a
range of emotions following an abortion. While relief is the most common
reported emotion, some women also experience feelings of sadness or
guilt. More efforts are therefore needed to help women deal with these
emotions – whether or not they rise to the level of "negative mental
health outcomes" – through post-abortion counseling or hotlines such
as Exhale and Backline.