Menstrual Cycle Informed Psychotherapy: Preliminary findings in Women with Spider Phobia.

BACKGROUND: Anxiety disorders are the most frequent mental disorders worldwide. Although exposure therapy is the gold-standard treatment for anxiety disorders, almost half of patients fail to achieve sufficient improvements. While much has been learned about for whom psychotherapy works and why, far less is understood about when it works. Emerging evidence indicates that estradiol and progesterone may affect fear extinction, yet studies examining the effects of menstrual cycle phase on exposure therapy outcomes remain lacking. This study is the first to investigate to what extent biologically informed menstrual cycle phase affects exposure therapy outcomes in women with spider phobia. METHOD: N=45 women with spider phobia in 1) the early to mid-follicular phase, 2) the mid-luteal phase, or 3) using hormonal contraceptives (HC), participated in a group-based exposure therapy. Symptoms were assessed at baseline, one-week post-therapy, and at 12-14 weeks follow-up, using the Spider Phobia Questionnaire (SPQ), the Fear of Spiders Questionnaire (FSQ), and a behavioral approach test (BAT). RESULTS: Both phobic fear and avoidance behavior improved significantly over time. Although improvement did not differ between menstrual cycle groups, higher progesterone levels on the day of exposure therapy were associated with less improvement in behavioral avoidance. CONCLUSION: The present findings provide preliminary evidence that ovarian hormones on the day of exposure therapy may affect exposure-based outcomes, particularly reductions in behavioral avoidance. More research in larger samples is needed to further investigate menstrual cycle phase effects in exposure-based treatment. If replicated, the findings would attest to the potential of bio-rhythm informed psychotherapy.