The effect of culture on how women experience menstruation: Jewish women and Mikvah. 
Mikvah is a practice in Judaism consisting of ritual bathing that occurs at the end of the menstrual period.  This study compared 161 married Jewish women, 82 mikvah users, and 79 non-users in order to learn how this ritual affects attitudes towards menstruation and the perception of menstrual and premenstrual distress.  Women participating in mikvah, a ritual that defines them as "unclean," were expected to have more negative conceptions of menstrual cycle symptomatology and more positive menstrual attitudes than women in the same culture not participating in this ritual.  These hypotheses were not supported by the findings.  What was found was a similarity between the two groups in attitudes towards menstruation, frequency and type of symptoms surrounding the menstrual period, and the degree to which any of these symptoms were experienced.