Effect of month of birth on the risk of suicide. Role of mood variation

n a multicentric study, by evaluating the psychological status of 2581 Italian women in postmenopause, we showed that anxiety and depression are minimal in women born in Autumn (lowest value November) and peak in women born in Spring (maximal value in March) (2). This seems to reflect quite nicely the seasonal pattern of suicide reported by Salib &Cortina- Boria (1). In our study, data were corrected for the month into which the psychological evaluation was indeed performed.Mood varies throughout the year, and seasonal rhythms of suicide (3,4), or of events related to low mood, as voluntary abortion, have been reported (4). Interestingly, these rhythms are similar to the one reported by Salib & Cortina-Boria for the month of birth and risk of suicide(1). It would be interesting to see whether data of this latter study would remain significant when corrected for the seasonal rhythm of suicide. If this is the case, the concordance between the seasonal rhythm of suicide, and the predisposition to suicide at birth, would suggest that the mechanisms predisposing the newborn to the risk of suicide are operative in the last part of pregnancy, very close to the timing of delivery.