RESUMO
BACKGROUND: The present study aimed to evaluate the impacts of lavender and metformin on polycystic ovary syndrome (PCOS) patients. METHODS: We performed a randomized, double-blind clinical trial including 68 females aged 18 to 45, fulfilling the Rotterdam criteria for PCOS. The patients were randomized to receive lavender (250 mg twice daily) or metformin (500 mg three times a day) for 90 days. The serum progesterone was measured at baseline and after 90 days, one week before their expected menstruation. Moreover, the length of the menstrual cycle was documented. RESULTS: Our results showed that lavender and metformin treatment notably increased the progesterone levels in PCOS patients (increasing from 0.35 (0.66) and 0.8 (0.69) to 2.5 (6.2) and 2.74 (6.27) ng/mL, respectively, P < 0.001). However, we found no significant differences between the increasing effects of both treatments on progesterone levels. In addition, all patients in the lavender or metformin groups had baseline progesterone levels <3 ng/mL, reaching 14 (45.2%) patients >3 ng/mL. Lavender and metformin remarkably attenuated the menstrual cycle length in PCOS patients (decreasing from 56.0 (20.0) and 60 (12.0) to 42.0 (5.0) and 50.0 (14.0) days, respectively, P < 0.001). Furthermore, the decreasing effects of lavender on the menstrual cycle length were greater than the metformin group; however, it was not statistically significant (P = 0.06). CONCLUSION: Lavender effectively increased progesterone levels and regulated the menstrual cycles in PCOS patients, similar to metformin. Therefore, lavender may be a promising candidate for the treatment of PCOS.