Serum allopregnanolone levels relate to FSFI score during the menstrual cycle

The aim of this study was to measure serum allopregnanolone levels and other hormones in women who completed the Female Sexual Function Index (FSFI; Rosen et al., 2000) during the follicular or the luteal phase of the menstrual cycle. Twenty-nine women with a regular menstrual cycle completed the FSFI during days 5-7 and days 19-21 of their menstrual cycles. We collected a blood sample on the same days so that we could determine levels of allopregnanolone (AP), dehydroepiandrosterone (DHEA), free testosterone (FreeT), androstenedione (A), and estradiol (E2); we stored serum at--20 degrees C until we assayed it. We performed statistical analyses by parametric and nonparametric comparisons and correlations, as appropriate. We found that the full FSFI score was 23 +/- 11.3 (mean +/- SD; 31% under 95% confidence interval = 18.7) in our study population. We also found a significant positive correlation between serum allopregnanolone levels and each FSFI domain, including full scale score (r = 0.47, p < 0.01), with the exception of pain. Similarly, we found a positive correlation between FreeT and each FSFI domain and full scale score (r = 0.55, p < 0.002). We found no significant correlation among FSFI scores and DHEA, A, or E2 plasma levels. It is interesting to note that FSFI full score was significantly higher (p < 0.04) in women tested in the luteal phase compared to women tested in the follicular phase. Serum allopregnanolone may be relevant to female sexuality directly or by its influence on a woman's general sense of well-being during the menstrual cycle. Further studies are required to test the hypothesis that high serum allopregnanolone levels in the luteal phase play a role in women's attitudes toward self-report questionnaires on sexual function.