Background: Studies from several countries suggest women differ in their preferred length of nonbleeding intervals, yet studies to date have not explored the social determinants of such preferences.
Method: We report results from a menstrual preference and social survey of 1207 healthy women in three age groups (18-20, 25-34 and 45-49 years) and two educational strata (high and low educational attainment), from Campinas (Brazil), Heidelberg (Germany) and Ann Arbor (USA) ( approximately 400 women from each country).
Results: Women's preferred length of nonbleeding intervals differed significantly between countries. In Ann Arbor, only 15.5% of women preferred to bleed monthly, vs. 30.2% in Heidelberg. In both Ann Arbor and Campinas, approximately one-third of women preferred to "never" have menses, compared to 8.2% in Heidelberg. Multivariate analyses indicated that country, church attendance, stress and menstrual pain were significant predictors of women's preferences.
Conclusion: The most common preference among women was to bleed once every 3 months, but preferences varied substantially by country groups. Preferences for nonbleeding intervals were, in part, explained by personal experiences of stress or menstrual pain, but unexplained cultural differences persist between country groups.