Various instruments have been used to detect postpartum depression (PPD). However, rather than waiting for depression to occur, can we possibly identify women during pregnancy who will go on to develop postpartum illness? If we could do that, we might be able to actually prevent the depression from occurring. Or at least, we could intervene in some way so that the depression would not significantly affect the mother and her family.
All women who give birth are at risk for postpartum depression. It is possible to identify women at greater risk – for example, women with a history of depression or women who have experienced postpartum illness after an earlier pregnancy. While screening for these groups of women will undoubtedly help us to catch many women who will go on to develop PPD, it will probably miss quite a few.
The Edinburgh Postnatal Depression Scale (EPDS) has been one of the most commonly used to screen for postpartum depression in a variety of settings. Researchers from the University of Groningen in the Netherlands tested the capacity of the EPDS used in pregnancy to predict which women would later experience PPD.
They assessed a group of 1620 pregnant women from the general population. Mean EPDS scores were significantly higher during pregnancy in women who experienced postpartum depressive symptoms than in those without postpartum symptoms (P < 0.001). Using the commonly used cut-off score of 13, the sensitivity was very low 16.8%; if this cut-off score was used, they would catch only 16.8% of the women who would go on to develop postpartum depression. The positive predictive value was also low (41.8%), indicating that less than half of the women who screened positive during pregnancy would go on to have PPD.
When they used a lower cut-off value (5), sensitivity was increased to 70.8% but the positive predictive value was unacceptably low (15.9%). The authors noted, however, that the negative predictive value was exceedingly high at 96.0%.
The authors concluded that the EPDS was not sufficiently accurate in predicting risk of postpartum depressive symptoms: “Nevertheless, when using the 5 cut-off value, it may be adequate for initial screening, followed by further assessments and possibly antenatal intervention when positive. Furthermore, when negative, women may be reassured that postpartum depressive symptoms are unlikely.”
Ruta Nonacs, MD PhD
Meijer J, Beijers C, van Pampus M, et al. Predictive accuracy of Edinburgh Postnatal Depression Scale assessment during pregnancy for the risk of developing postpartum depressive symptoms: a prospective cohort study. BJOG. 2014 Apr 7. [Epub ahead of print]