Reproductive factors in females with recurrent aphthous stomatitis

Background: Recurrent aphthous stomatitis (RAS) is a painful oral wound affecting 40% of the U.S. population; however, its etiology is unclear. Female RAS patients have reported more frequent RAS at the beginning of their menstrual cycle.

Objective: To investigate the association between certain female reproductive factors and RAS onset.

Method: Data were collected at the University of Florida from June 2006 to April 2011 through questionnaires and oral exams. Participants were not pregnant and had either active aphthae (less than 72 hours’ duration) or a negative oral exam (inactive RAS patients or controls that never had RAS). Data were stored in REDCap and analyzed using chi-squared tests and general linear models in SAS v9.3.

Results: We recruited 151 female participants (21 active, 54 inactive and 76 controls) aged 17-43 years old (23±5, mean±SD), 71% White, and 13% Hispanic. A similar proportion of females in the three groups reported regular periods (86-90%; p=0.77), contraceptive use (33-48%; p=0.52), and menstrual symptoms (71-80%; p=0.71). Cycle length was also similar (28-31 days; p=0.10). The average time between the first day of the last menstruation and the visit (or RAS onset) was longer for patients with vs. without active RAS (18±9 vs. 14±9 days, respectively; p=0.04), although this association was no longer significant after adjustment for age, menstrual cycle length and contraceptive use.

Conclusion: RAS did not occur more frequently at the beginning of the menstrual cycle. Results should be interpreted with caution because of patients’ ability to change the date of visit.