I just found this paper from 2005, that states that abortion does not influence on depression rates. It suggests that some studies show otherwise, since women who selfreport their abortions might also report more on depression symptoms
paper writes:
Indeed, finding
that depression scores for the group that refused to fill out a
confidential abortion card were significantly lower than for the
reporting group suggests that women who are willing to disclose
abortion are also more willing to disclose stigmatising mental
health problems, such as depressive symptoms”that is, they
exhibit a form of “over-reporting bias.”
http://bmj.bmjjournals.com/...dpdf/bmj.38623.532384.55v1.pdf
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