About half of all pregnancies in the U.S. are unintended, and 40 percent of these are terminated by abortion. Those ideologically opposed to abortion often argue that the experience is psychologically harmful to women, citing reports of a link between abortion and later mental health problems such as depression. Now, after an exhaustive review of the literature, experts conclude that the best scientific evidence indicates that having a single abortion does not increase a woman’s risk of emotional problems.

In 2006 the American Psychological Association (APA) assembled a task force of researchers with wide-ranging expertise to evaluate all peer-reviewed studies published in English since 1989 (when the last such review was conducted) that compared the mental health of women who had an abortion with that of other women. It is clear that after an abortion some women experience sadness and grief and, in some cases, clinically significant disorders such as depression or anxiety. But the task force concluded in August that “among women who have a single, legal, first-trimester abortion of an unplanned pregnancy for nontherapeutic reasons, the relative risks of mental health problems are no greater than the risks among women who deliver an unplanned pregnancy.” The evidence for the risk associated with multiple abortions is more equivocal.

In its report the APA highlighted the often severe methodological shortcomings that plagued much of the research. “Very rarely does a study include an appropriate comparison group,” laments task force chair Brenda Major, a psychologist at the University of California, Santa Barbara. The only suitable comparison groups include women who carry their unwanted pregnancy to term and either raise the child or give it up for adoption, Major explains, because these are the two main options in addition to abortion that a woman has once she is faced with an unwanted pregnancy.

Many studies did not adequately control for other variables known to be associated with psychological well-being, including poverty, prior exposure to violence, and a history of mental health problems or substance abuse. Failure to parse out the effects of these co-occurring risk factors, the APA explains, can lead to reports of associations between mental health and abortion history that are misleading.

The task force called for more rigorous studies that try to disentangle such confounding factors. “It’s not that we need more research,” Major warns. “We need better research.” Studies should be longitudinal—following women over time—and include larger, more representative samples. Furthermore, authors need to more adequately assess the degree to which a pregnancy is intended or wanted. A woman who terminates a wanted pregnancy because of a fetal abnormality, for example, may suffer more emotionally than someone who aborts because of an unplanned pregnancy.

The reviewers identified several risk factors for women in the U.S. that were predictive of adverse reactions subsequent to abortion, including perceptions of stigma, a need for secrecy, low social support and personality traits such as coping style. The strongest predictor of postabortion mental health is a woman’s preexisting mental health.

Major and her colleagues believe future research should focus on understanding the conditions that contribute to negative emotional responses and on bolstering women’s resilience. Emphasizing the “diversity and complexity of women and their circumstances,” the report cautions that any global statements about the psychological impact of abortion have the potential to be misleading.

Note: This article was originally printed with the title, "Abortion Risk Reviewed".