Pain as a confounding factor in postnatal depression screening

Postnatal depression (PND) is one of the most serious complications following delivery in developed countries today. Thus, early screening strategies by first-line healthcare workers are of primary importance. Pain following childbirth has been proposed as a possible risk-marker for later depressive disorder. We tested this assumption and explored the possible link between pain and overestimation of PND risk in routine clinical screenings.

We assessed 320 women between the third and fifth day after delivery as well as at 8 weeks post-partum (PP). Midwives were asked to evaluate the risk of later PND upon discharge from the maternity unit; additionally, pain measurements were obtained using the Visual Analogic Scale (VAS) over the same time period. A stepwise logistic regression analysis was performed to identify the risk markers linked to a positive depressive disorder diagnosis (according to the MINI-DSM-IV) at 8 weeks PP.

Multivariate risk analysis showed no statistical link between physical pain shortly after childbirth and subsequent PND diagnosis at 8 weeks PP. However, VAS measurements for pain were significantly higher for women that the midwives estimated to be at risk for PND (|Z| = 2.78, p = 0.005), suggesting the routine clinical screening for PND is susceptible for false-positives. Psychiatrists should encourage midwives to have an empathetic approach, to increase the detection as well as treatment of mental and physical suffering in early postpartum. At the same time, adequate education programmes for early PND screening should be proposed to non-psychiatric staffs to demonstrate that women at risk of PND often show minimal physical symptoms.