Measurement of tryptophan, kynurenine and neopterin in women with and without postpartum blues

Abstract Background Activation of the tryptophan-degrading enzyme indoleamine (2,3)-dioxygenase was demonstrated to be critically involved in tolerance induction to prevent fetal rejection. Our study was designed to examine alterations of tryptophan and its catabolic product kynurenine in the postpartum period and to compare them to neopterin as an immunological marker. Methods 95 healthy women delivering without complications provided blood during labour, and 2 and 4 days after birth. The blood samples were analysed for concentrations of tryptophan, kynurenine and neopterin. Women were asked to perform the Edinburgh Postnatal Depression Scale (EPDS) on days 2 and 4. Results In women without blues symptoms ( n =86) tryptophan concentrations increased within 2 days after birth, whereas they did not change in women with postpartum blues ( n =9; 9.5%). The group difference reached statistical significance ( p p p Limitations Our study population had a low prevalence of postpartum blues symptoms. Conclusion Low postpartal mood is associated with continuously low serum tryptophan after delivery due to an increased degradation to kynurenine, but is independent of the postpartal course of neopterin.