Women who have abortions do not experience an increased risk of mental illness following the procedure, according to a multiyear Danish population study. The study by Trine Munk-Olsen, Ph.D., and colleagues was published in the January 27 New England Journal of Medicine.

"The finding that the incidence rate of psychiatric contact was similar before and after a first-trimester abortion does not support the hypothesis that there is an increased risk of mental disorders after a first-trimester induced abortion," the researchers concluded.

The scope of the Danish study was impressive. It reviewed data for 954,000 girls and women, relying on Denmark's comprehensive central statistical system to track by personal identification number which individuals gave birth, which had abortions, and which sought mental health care. The researchers tracked all women over age 15 who had had a first childbirth or a first-trimester abortion from 1995 to 2007.

The researchers found that taken as a population, women in the study who gave birth were likely to increase their use of mental health services. The number of women who sought psychiatric help spiked during the month after childbirth, to 3.3 times the number before childbirth. The incidence then gradually dropped over the following 10 months.

An earlier study published in 2006 by Munk-Olsen and colleagues indicated that new mothers in the first nine days after childbirth had a large increase in psychiatric hospital admissions, and that percentage doubled during the 10th to 19th day after childbirth. After day 20, mental health visits decreased considerably.

Overall, however, the percentages of women who sought mental health care both before and after abortion was higher than the percentage among women who gave birth, though no spike in the percentage was seen postabortion. During the study years, 84,620 girls and women had a first-time, first-trimester induced abortion. Of those, 868 (1 percent) had a first psychiatric contact during the nine months before the abortion. The researchers chose a nine-month period to parallel the typical nine-month gestation for women who carried to term. Among women who had abortions, 1,277 (1.5 percent) had a first psychiatric contact within 12 months after the abortion. The incidence of psychiatric contact fluctuated during the 12 months, but did not show a clear trend.

During the same study period, 280,930 girls and women gave birth to their first live-born child. Of those, 790 (0.3 percent) had a first-time psychiatric contact in the nine months before delivery, as did 1,916 (0.7 percent) in the 12 months after delivery. The data included both inpatient and outpatient psychiatric contacts.

In other words, the women who gave birth had a sharp increase in seeking mental health care after childbirth. However, except for the first month after giving birth, the percentage of birth mothers seeking psychiatric care was well below the percentage of women who obtained abortions and sought psychiatric care.

The difference between the women who had abortions and those who gave birth is quite understandable, said Nada Stotland, M.D., a former APA president and an authority on the psychiatric issues surrounding abortion. Stotland told Psychiatric News that women who have induced abortions experience a stressful one-time event, while "after birth you have a very demanding person to take care of," which often results in ongoing stress. Moreover, in Scandinavia, with its generous maternity leave and free medical care, "people have the time and opportunity to get mental health care."

Stotland is a professor at Rush Medical College in Chicago and for seven years chaired the APA Committee on Women.

In the United States, Stotland suggested, it's likely that stress levels among new mothers are higher than those in Denmark. "Because we often don't have maternity leave, there's a disincentive for women to seek mental health care. Women complain that they are terribly stressed."

Because abortion is a politically charged issue in the United States, studies such as the current one can have political implications and can themselves become the subject of vigorous debate.

Stotland noted, for example, that in the United States there are active efforts to recruit women to report that they have experienced mental illness after abortion. "There's an invented term—‘post-abortion syndrome’—but that's not recognized by any medical authority."

Stotland added, "Telling women that abortion causes mental illness causes increased mental illness. So these allegations are not only incorrect—they are damaging. If a woman is in a situation where abortion is frowned upon, she's more likely to experience mental illness."

According to the Danish study, some earlier reports that had described, for example, an increased risk of depression among women who had abortions were biased or otherwise flawed.

The researchers explained, "The incidence rate of psychiatric contact was higher among girls and women who underwent an abortion than among those who underwent delivery, but this relationship was evident before the abortion or childbirth occurred … . It seems likely that girls and women having induced abortions constitute a population with higher psychiatric morbidity. We interpret this as a selection phenomenon rather than a causal association."

"Any propensity toward mental health disorders in girls or women who have induced abortions predates the abortion and indeed may make termination of the pregnancy more likely," the researchers suggested.

Along these lines, Stotland noted, "Mental illness is not caused by abortion but may be caused by the circumstances that lead women to have an abortion, such as being abandoned by their partner when they become pregnant."

While women and girls who have abortions often have feelings of sadness, loss, or regret, the researchers pointed out that those feelings, "though unpleasant, do not necessarily signify a mental disorder." Some earlier, flawed studies of abortion and mental health "failed to distinguish between mental health diagnoses such as depression and psychosis" and more normal feelings such as regret, they noted.

Neurotic, stress-related, or somatoform disorders were the ones most often diagnosed among Danish girls and women who sought mental health care in the 12 months after an abortion.

The most common diagnoses among women who gave birth were also neurotic, stress-related, and somatoform disorders, as well as affective disorders. In the 30 days after childbirth, puerperal disorders and adjustment disorders were especially prevalent, the researchers noted.

An abstract of "Induced First-Trimester Abortion and Risk of Mental Disorder" is posted at <www.nejm.org/doi/full/10.1056/NEJMoa0905882>.