Daily fluctuations in ocular surface symptoms during the normal menstrual cycle and with the use of oral contraceptives.

PURPOSE

Women are more prone to ocular surface symptoms and circulating estrogen levels have been implicated. Fluctuations in estrogen during the menstrual cycle may influence ocular symptoms but existing research is incomplete and conflicting, partly due to paucity of validated questionnaires to assess daily ocular symptoms. This study aimed to evaluate daily fluctuations in ocular symptoms across a complete menstrual cycle and to compare symptoms in normally menstruating women and women using the combined oral contraceptive pill (OCP).

METHODS

To do this, a short online tool to assess daily symptoms was developed. 36 normally menstruating women and 36 women using the combined OCP were recruited. A two-item questionnaire, the Instant Ocular Symptoms Survey (IOSS) was developed and administered on a smartphone platform every day for 40 days. Linear mixed model analysis was used to examine differences in symptom scores over time and between groups.

RESULTS

The IOSS was found to be effective for measuring instantaneous symptoms, exhibiting good diagnostic abilities and repeatability. (AUC ± SE = 0.80 ± 0.07 and ICC = 0.75). Daily ocular symptoms showed a cyclic fluctuation across the cycle (p = 0.004) and highest symptoms were recorded on day 2 of the cycle when estrogen levels are lowest. Symptom scores were significantly higher in the OCP group (p = 0.02).

CONCLUSIONS

Effects of menstrual phase and OCP use should be considered in the interpretation of ocular symptoms in clinical practice. These findings enhance the current understandings of ocular surface and systemic pain during menstrual cycle.