Background: Neurosteroids such as allopregnanolone and pregnanolone are suggested to be of importance for the pathophysiology of premenstrual dysphoric disorder. The aim of this study was to investigate whether the luteal-phase serum concentrations of these neurosteroids are associated with improvement of premenstrual symptoms in 12 women with severe premenstrual syndrome after treatment with low-dose gonadotropin-releasing hormone agonist and placebo.
Methods: Daily ratings for mood and physical symptoms were made prior to treatment and throughout the study. Serum progesterone, allopregnanolone and pregnanolone were assessed in the luteal phase (cycle day -9 to cycle day -1). Based on their symptom ratings, subjects were grouped as either buserelin responders (n = 6) or placebo responders (n = 6).
Results: Buserelin responders displayed decreased levels of allopregnanolone (p < 0.05) and progesterone (p < 0.05) in parallel with improvement of symptoms. During the placebo treatment, the placebo responders had lower serum allopregnanolone concentrations than buserelin responders (p < 0.05). This was associated with improvement in symptoms compared with pre-treatment ratings.
Conclusion: Treatment response, whether induced by buserelin or placebo, appears to be associated with a decrease in allopregnanolone concentration.