Stress and immune mediators in miscarriage

BACKGROUND: Stress is thought to be abortogenic and psycho-neuro-immunologi cal pathways have been suggested to be involved in triggering miscarriages. From experiments in pregnant mice exposed to stress some insights into the underlying mechanisms have been gained, delineating immunological imbalanc es as a cause of pregnancy failure. In order to test the validity of the co nclusions drawn from murine experiments and the role of stress in human pre gnancy loss, the following study was performed. METHODS: We used an establi shed perceived stress questionnaire and measured the stress score of women with a confirmed diagnosis of first trimester spontaneous abortion (n = 94) , Decidual tissue was investigated by immunohistochemistry and in-situ hybr idization to detect the presence and distribution of immunocompetent decidu al cells [CD56(+) natural killer (NK) cells, CD8(+) and CD3(+) T cells, try ptase(+) mast cells (MCT+) and tumour necrosis factor (TNF)-alpha (+) cells ]. The patient cohort was divided into women experiencing low or high level s of stress. RESULTS: In the decidua of women with high stress scores we ob served significantly higher numbers of MCT+, CD8(+) T cells and TNF-alpha ( +) cells per mm(2) tissue (P less than or equal to 0.05), No significant di fferences between individuals with lower or higher stress scores could be o bserved with respect to decidual CD56(+) NK and CD3(+) T cells. CONCLUSIONS : Using a questionnaire to score perceived stress in humans may be a valid approach to assess non-biased stress scores. Stress-triggered abortion in h umans, identified by a questionnaire, can be linked to immunological imbala nces.