(Photo: Molly Belle/Unsplash)

The notion that having an abortion puts women at higher risk of depression has circulated widely among anti-abortion activists. Even Supreme Court Justice Anthony Kennedy, long considered a "swing vote" on the emotionally charged topic, has argued that states should be allowed to limit access to the procedure to protect women from "depression and loss of esteem."

One small problem: A long line of research has found no basis for that assertion. Now, a new study provides further evidence that there is no link between depression and abortion.

"Policies based on the notion that abortion harms women's mental health are misinformed," lead author Julia Steinberg of the University of Maryland School of Public Health said in announcing the findings. "Our findings show that women were not more likely to suffer from depression after an abortion compared to beforehand."

The study, in the journal JAMA Psychiatry, utilized data on nearly 400,000 women born in Denmark between 1980 and 1994. Between the years 2000 and 2012, 85,592 of them gave birth for the first time, while 30,834 had a first-trimester first abortion.

Fifteen percent of the women—59,465, to be exact—received a first-time prescription for an antidepressant during that time period. The researchers looked at who they were, and whether either abortion or childbirth increased their chances of taking such a drug.

"Women who have abortions are more likely to use antidepressants compared with women who do not have abortions," they report. Further analysis, however, shows this "is not attributable to having had an abortion," but rather to "preexisting mental health conditions" and other factors that predate the decision to terminate one's pregnancy.

Their "increased risk of depression did not change from the year before to the year after an abortion," the researchers report. "And contrary to previous claims that abortion has long-term adverse effects, the risk of depression decreased as more time elapsed after the abortion."

This suggests the argument of anti-abortion activists may be precisely backwards. Rather than abortion causing mental-health problems, it is more plausible that "mental health problems may lead women to have unintended pregnancies and abortions," they write.

Altogether, the findings indicate that, when abortion is a viable option, and the "life circumstances" of those women who choose pregnancy vs. abortion are similar, "having an abortion is not associated with a higher likelihood of mental health problems."

The researchers also noted an additional trend: Among new mothers, "the risk of antidepressant use increased" as more time passed following giving birth. Perhaps it's the stress of raising a child—not the after-effects of an abortion—that can take a toll on a woman's mental health.