Day-to-day co-variations of psychological and physical symptoms of the menstrual cycle: Insights to individual differences in steroid reactivity.

The associations between physical and psychological symptoms of the menstrual cycle have not been carefully studied in past research, but may lead to a better understanding of the underlying mechanisms of these symptoms. The present study examines the day-to-day covariations among physical and psychological symptoms of the menstrual cycle. These symptoms were evaluated on a daily basis across one entire menstrual cycle, with a non-clinical sample of 92 university students. Results showed that headaches, gastrointestinal problems, lower abdominal bloating, skin changes, and breast changes, were all significantly associated with higher levels of psychological symptoms; whereas back and joint pain, lower abdominal cramps, cervical mucous, and menstrual flow, were not associated with psychological symptoms. However, significant differences in these associations were observed across individuals for back and joint pain, headaches, lower abdominal cramps, skin changes, and menstrual flow: Whereas some women demonstrated higher levels of psychological symptoms associated with these physical symptoms, other women demonstrated lower levels of psychological symptoms. Finally, correlations among the associations between physical and psychological symptoms (slopes) demonstrated clear differences across the different physical symptoms. These results indicate that, although higher levels of some physical symptoms are associated with higher levels of psychological symptoms, there are significant differences in the magnitude and direction of these relations across individuals. Further consideration of physical symptoms may provide useful information for understanding individual differences in symptom profiles and response to steroid fluctuations, and for improving differential diagnosis and treatment planning and evaluation.