Many women report forgetfulness and changes in memory as they transition to menopause. But studies that target participants who are 65 and older do not account for cognitive changes that may take place decades earlier in a woman’s life.

By studying women ages 45 to 55, investigators at Harvard-affiliated Brigham and Women’s Hospital (BWH) have found that reproductive stage, not simply chronological age, may contribute to changes in memory and brain function. Their findings will be published Wednesday in The Journal of Neuroscience.