Tryptophan, Cortisol and Puerperal Mood

Abstract

Plasma cortisol, free and total tryptophan were determined in 71 human subjects on 8 occasions between 36 wk gestation and 6 wk post-partum. Affect was measured by rating scales and clinical interview. Subjects [28] experienced post-partum blues. Seasonal variation occurred in the incidence of blues and in cortisol and free tryptophan levels. Puerperally-depressed mood was correlated with high cortisol at 38 wk irrespective of season. Free tryptophan was reduced in blues subjects but only at the time of year when free tryptophan was normally high. Total tryptophan was low antenatally; a rapid rise on days land 2 postpartum was superimposed on a slower return to normal. This initial peak was clearly absent in 37% of subjects. Its absence was significantly related to occurrence of post-partum blues and of complaints of depression in the ensuing 6 mo. The possible occurrence of an occult disturbance of tryptophan handling in subjects susceptible to depression was discussed.