Oestradiol and psychosis: clinical findings and biological mechanisms

Female sex steroids easily access the central nervous system and modulate a number of intracerebral processes via their specific receptors. Oestradiol is the biologically dominant female sex steroid and has been implicated in the aetiology and course of psychotic illnesses. There is evidence for interaction between oestradiol and several neurobiological systems that have been implicated in the pathogenesis of psychotic illnesses. Clinical studies have indicated that psychosis, and in particular schizophrenia, is associated with reduced ovarian function and that this may be inherent to the illness itself. In schizophrenia several studies have suggested a therapeutic effect of oestradiol and selective oestrogen modulators although research is still at an early stage. In bipolar disorder, the relationship between childbirth and first onsets or recurrences is one of the most reproducible findings in psychiatric research. Whether or not the rapid fall of oestrogens is the mediating mechanism is not yet clear but preliminary oestrogen treatment studies commenced immediately after childbirth are promising. Outside the perinatal context, tamoxifen, a selective oestrogen receptor modulator, has shown strong antimanic effects although further studies are necessary to test an effect in larger samples. Hormonal treatments should not yet be used in standard care but could be considered in women with treatment resistant psychoses.