Predictors of visually induced motion sickness in women

Background: Visually induced motion sickness (VIMS) is commonly experienced when visual motion information is in conflict with motion information provided by the vestibular system and/or tactile and kinesthetic senses. According to some studies, women experience higher levels of VIMS than men, whereas other studies do not find this to be the case. Hypothesis: This study investigated whether gender differences can be attributed to changes in VIMS-susceptibility due to the menstrual cycle and perceived menstrual pain. We hypothesized that higher perceived menstrual pain correlates positively with VIMS susceptibility. Methods: We measured the influence of estimated concentrations of four sex hormones and menstrual pain, on the magnitude of self-reported VIMS levels and on measured postural stability in 56 participants. They were confronted with a continuous ten-minute recording of a bike ride across mountainous terrain. Subjective VIMS was measured at one-minute intervals during stimulus presentation using the Fast Motion Sickness (FMS) Scale; postural sway was recorded immediately before and after stimulus presentation. Results: Correlation between peak FMS scores and perceived menstrual pain was high. Furthermore, significant differences between women with severe menstrual pain on the one hand and women with low pain and men on the other hand were found. Conclusions: Our findings suggest a shared link between VIMS and menstrual pain. Further research should investigate pain sensitivity as a general predictor for VIMS.