A Reanalysis of Mental Disorders Risk Following First-Trimester Abortions in Denmark.

Background: A previous Danish study of monthly and tri-monthly rates of first-time psychiatric contact following first induced abortions reported higher rates compared to first live births but similar rates compared to nine months pre-abortion. Therefore, the researchers concluded abortion has no independent effect on mental health; any differences between psychiatric contacts after abortion and delivery are entirely attributable to pre-existing mental health differences. However, these conclusions are inconsistent with similar studies that used longer time frames. Reanalysis of the published Danish data over slightly longer time frames may reconcile this discordance.

Method: Monthly and tri-monthly data was extracted for reanalysis of cumulative effects over nine- and twelvemonths post-abortion.

Results: Across all psychiatric diagnoses, cumulative average monthly rate of first-time psychiatric contact increased from an odds ratio of 1.12 (95% CI: 1.02 to 1.22) at 9-months to 1.49 (95% CI: 1.37 to 1.63) at 12 months post-abortion as compared to the 9 months pre-abortion rate. At 12 months post-abortion, first-time psychiatric contact was higher across all four diagnostic groupings and highest for personality or behavioral disorders (OR=1.87; 95% CI:1.48 to 2.36) and neurotic, stress related, or somatoform disorders (OR=1.60; 95% CI: 1.41 to 1.81).

Conclusions: Our reanalysis revealed that the Danish data is consistent with the larger body of both record-based and survey- based studies when viewed over periods of observation of at least nine months. Longer periods of observation are necessary to capture both anniversary reactions and the exhaustion of coping mechanisms which may delay observation of post-abortion effects.