In a study of healthy postmenopausal women, reproductive life events related to sex hormones, including earlier age at menarche, later age at last pregnancy, length of reproductive period, and use of oral contraceptives were positively related to aspects of cognition in later life.
Investigators found that age at menarche greater than or equal to 13 years of age was inversely linked with cognition, and last pregnancy after age 35 was positively linked with verbal memory. Use of hormonal contraceptives was positively associated with cognition and verbal memory. The association between hormonal contraceptive use and verbal memory and executive functions was strongest for more than 10 years of use. Reproductive period was positively linked with cognition and executive functions.
"While it is not enough to suggest that women wait until after 35 years of age to close their family growth, our finding of a positive effect of later age at last pregnancy on late-life cognition is novel and substantial. More research is warranted to evaluate the underlying mechanism of this phenomenon and also to understand the role of age at first pregnancy in this phenomenon," said Dr. Roksana Karim, lead author of the Journal of the American Geriatrics Society study.