No drop in women’s brain function during periods: study

Contrary to popular belief, menstruation does not impair women’s cognitive performance, new research suggests.

The study found that while many women report feeling worse during their period — experiencing symptoms such as headaches, pain, or brain fog — these sensations do not translate into poorer attention or slower reaction times.

The research, published in Sports Medicine – Open, tracked 54 women aged 18 to 40 across four key phases of their menstrual cycle: menstruation, late follicular, ovulation, and mid-luteal. Participants completed mood assessments and cognitive tests during each phase to measure focus, reaction time, and accuracy.

Results showed that brain function did fluctuate slightly across the cycle, but not during menstruation. Women’s reaction times were actually at their best around ovulation, while slower responses and more errors were recorded during the mid-luteal and late follicular phases.

The differences measured were minimal — only a few milliseconds — and unlikely to affect daily activities. However, researchers noted that in sports where even small reaction time differences can influence performance or injury risk, these findings could be significant.

The study also highlighted the role of physical activity. Participants who led more active lifestyles had faster reaction times and made fewer impulsive errors compared to those who were less active, regardless of their menstrual phase.

Overall, the findings challenge long-held assumptions about women’s mental performance during their period and suggest that while physical discomfort and mood changes are real, they do not hinder cognitive ability. Regular physical activity, on the other hand, appears to offer a meaningful boost to brain function throughout the menstrual cycle.