Testosterone-to-estradiol ratio and self-reported decreased libido among men seeking sexual medicine care: a retrospective study

PURPOSE: To evaluate the correlation between loss of libido and hormonal profile (HP), including the Total Testosterone (T) / Estradiol (E2) ratio, at a tertiary reference center in andrology and sexual medicine. METHODS: A retrospective analysis of medical records from patients experiencing sexual dysfunction in a tertiary care center was performed. Patients were systematically asked whether they perceived a loss of libido using the following question: "Do you believe your libido or sexual desire has decreased over the last few months?" Patients had morning (between 6:00 and 10:00 a.m.) HP checked (Total testosterone (T), Prolactin (P), Luteinizing Hormone (LH), and E2. HP was divided into four different groups: Low T (T<300 ng/dl); Normal T (T≥300 ng/dl); standard T/E2 ratio (> 10); and Low T/E2 ratio (≤ 10). RESULTS: We evaluated 228 patients, and the mean (± SD) age was 61 ± 10 years. 30% of the patients complained about low libido. Hormone analysis showed that 21% had low T levels, while 22% had a low T/E2 ratio. Among those with low T levels, 42% reported low libido (OR 1.9; 95% IC 1.08-3.73; p = 0.01). Conversely, in the group with a low T/E2 ratio, 52% experienced a decrease in sexual desire (OR 3.47; 95% IC 1.79-6.46; p = 0.001). In multivariate analysis, after adjusting for age, the T/E2 ratio was associated with decreased libido regardless of T status. CONCLUSION: Low T levels and low T/E2 ratios were strongly correlated with decreased libido in our sample of men seeking care at a tertiary andrology and sexual medicine center. Further studies are needed to confirm our results as well as to evaluate the lifestyle and metabolic factors with the hormonal status of these patients with low sexual desire.