Investigations of visual changes associated with the menstrual cycle and pregnancy

Background: There is a paucity of information on visual effects associated with the menstrual cycle and pregnancy and the current literature is equivocal. There are currently no guidelines for eyecare professionals on when it is appropriate to prescribe spectacles.
Aim: To investigate, through scoping literature reviews and quantitative data analyses, possible visual changes and dry eye symptoms which are associated with the menstrual cycle and pregnancy.
Setting: The COVID pandemic only permitted online self-reported measurements using validated vision and dry eye questionnaires and a visual acuity test at peak progesterone, peak oestrogen, and menstruation stages of the menstrual cycle.
Methods: Scoping literature reviews provided an update on current knowledge. Novel online methodologies were developed, including use of eConsent and Web Apps for collecting data from the RAND NEI RQL 42, Sande dye questionnaires and the FrACT visual acuity test.
Participants: Despite wide promotion through multiple routes, only 44 participants were recruited of which only 15 completed data collection at 2 or more stages of the menstrual cycle.
Results: Baseline data on menarche and menstrual cycle duration is consistent with current literature. No statistically significant effects (tested using Wilcoxon’s Signed Rank test) were found for five NEI RQL 42 subscales, Sande Dry questionnaire or the FrACT visual acuity measurements studied. Using Cohens d values for effect sizes, the far vision and Sande dry eye question 2 subscales, for the 2 questionnaires only completed cohort, had large effect sizes with the Sande dry eye question 2 subscale having a medium effect size for the all 3 questionnaires completed cohort. There was a trend suggesting greater visual difficulties and dry eye symptoms around the time of peak oestrogen which reduce towards menstruation.
Conclusion: Despite the disappointing lack of statistically significant findings, possibly due to insufficient data, the observed effect sizes for the far vision, glare and dry eye subscales indicate that future research in these areas might be most fruitful when considering visual changes associated with the menstrual cycle and pregnancy. This thesis provides the latest knowledge together with novel online methodologies that would enable further practice-based study of this topic and many others like it.