The validity of DSM symptoms for depression and anxiety disorders during pregnancy

Background: The applicability of the symptom criteria for diagnostic mood and anxiety disorders has in recent times been questioned for women in the perinatal period, due to the overlap of diagnostic symptoms with normal symptoms due to the physical changes of pregnancy or postpartum, (e.g., sleep difficulties). Method: 118 women in their second or early third trimester of pregnancy participated in a telephone interview that included the depression and anxiety modules of the MINI diagnostic interview, and an attributional probe question asking the woman whether endorsement of a symptom was due to the physical changes of her pregnancy or due to her mood or worries. Results: 66% of pregnant women who met criteria for major depression reported that a sufficient number of their symptoms were due to the normal physical changes of their pregnancy, such that they would no longer meet criteria for a diagnosis of major depression. Attributional probing resulted in the rate of major depression falling from 6.8% to 1.7%. The impact on anxiety disorders appears to be less. Limitations: An important issue is whether women's attributional perceptions are valid, though the face validity of some of their responses means that credence should be given to the findings. In addition, it would be useful from a validity perspective to undertake the same attributional probing with other populations where symptom presence is most likely due to mood, such as unemployed or recently separated adults without physical complaints. Conclusion: Rates of depressive disorders in pregnancy, using DSM symptom criteria, are significantly over-estimated due to the natural occurrence of many of the symptoms as a result of the pregnancy. Rates of anxiety disorders are also inflated, but to a lesser degree. This means that the validation of self-report mood measures, typically done against DSM diagnoses, is likely to have produced erroneous findings (e.g., optimum cut-off scores). It is probable that a similar finding would be obtained for the postpartum period. Thus future use of DSM symptom criteria for depression and anxiety in perinatal mental health work should use some form of attributional probing question to more accurately understand the applicability of symptoms to a diagnosis in this population.