Disorders of the menstrual cycle in airline stewardesses.

Of 200 airline stewardesses, 39% underwent unfavourable changes in the menstrual cycle after commencing aeronautical activities while 11% who had previous disorders healed soon after joining the company. Although 48% of the stewardesses underwent changes in menstruation during flight, in about half of these the menstrual flow increased and in the other half it decreased or disappeared, only to reappear with greater intensity after the flight; 38% of the stewardesses manifected suffering from pelvic discomfort after long flights. Sufficient research in this field has not been done. Therefore, it is difficult to trace the exact origin and mechanism of these changes in the menstrual cycle. Stress and internal desynchronitation due to disruption of circadian rhythm may intervene in generating these disorders.