Objective To investigate the clinical efficacy and related mechanism of melatonin in the treatment of premature ovarian insufficiency (POI).

Methods A total of 100 POI patients in gynecological department were retrospectively selected and were randomly divided into control group(treated by traditional hormone replacement method, n=50)and test group (additionally treated by melatonin on basis of the control group, n=50). The basic data, serum hormone levels including follicle stimulating hormone (FSH), luteinizing hormone(LH), estradiol (E₂) and anti-Mullerian hormone(AMH), the levels of oxidative stress including reactive oxygen species(ROS) and total antioxidant capacity assay kit (T-AOC) were recorded. Meanwhile, the improvement of menstruation and the incidence of adverse effects in both groups were compared during follow-up.

Results There were no significant differences in age, body mass index, menstrual cycle and fertility requirements between the two groups (P > 0.05). Compared with the control group, serum FSH and ROS levels were significantly decreased, while E₂ and AMH increased after 3 and 6 months in the test group(P < 0.05). After 1 month, 3 and 6 months of treatment, T-AOC level in test group was higher than that in control group (P < 0.05). After treatment, there were no statistical significance differences in the improvement of menstruation and the incidence of adverse reactions between two groups (P > 0.05).

Conclusion The combination of hormone replacement therapy and melatonin can reduce the level of oxidative stress and improve serum sex hormone levels and menstruation, without increasing the risk of adverse reactions. Therefore, this regimen is a safe and effective method.