A double-blind, randomised controlled trial was carried out to evaluate the effect of lavender essential oil inhilation on the sleep and menopausal symptoms of postmenopausal women with insomnia. 

35 postmenopausal women participated in the study, all of whom had a diagnosis of insomnia. 17 were placed in the Aroma Group (AG) and 18 in the Placebo Group (PG).

The AG group inhaled lavendar essential oil and the PG participants inhaled sunflower oil for 29 days. All participants were given sleep hygiene guidelines before the trial took place and weekly followups, with evaluation performed before and after intervention. Sleep quality was measured with the Pittsburgh Sleep Quality Index, while other data was collected to measure the severity of insomnia, anxiety and depression symptoms, and postmenopausal symptoms.

The results showed no significant differences between the groups in terms of sleep quality; however, an improvement was seen in wake after sleep onset in the AG group. The AG group also showed a significant decrease in sleep onset latency, depression levels, hot flashes, postmenopausal symptoms, and increased sleep efficiency.

 Original study