Key TakeawaysLonger reproductive lifespans may be linked to better brain blood vessel healthWomen who used birth control and later hormone therapy had the least brain vessel damageEstrogen may protect brain health, but more research is needed.FRIDAY, Nov. 6, 2026 (HealthDay News) — A new study suggests a woman's reproductive history may play an important role in her brain health later in life."Women are affected by Alzheimer's disease more often than men. This may be related, in part, to fluctuations in estrogen levels throughout life," said study author Anna Marseglia, an assistant professor at the Karolinska Institutet in Stockholm."Estrogen is known to have protective effects on both neuronal cells and blood vessels in the brain," she added in a news release. "However, its potential role in women's cerebrovascular health in later life has been largely understudied."Researchers studied 352 women, examining their lifetime estrogen exposure and brain scans taken in their 70s.They found participants with longer reproductive lifespans — from their first period to menopause — had fewer signs of damage to the brain's small blood vessels."The most favorable vascular brain health was observed among women who had used oral contraceptives during their reproductive years and later received menopausal hormone therapy," Marseglia said.These women had the least small vessel disease. Menopausal hormone therapy was also associated with fewer brain microbleeds.However, these associations do not prove that a longer reproductive lifespan or hormone use directly protects the brain. More research, including clinical trials, is needed.The study was published Nov. 4 in the journal Neurology.More informationThe Alzheimer's Association has more on brain health.SOURCE: HealthDay TV, Nov. 6, 2026 .What This Means For YouA woman's lifetime estrogen exposure, including hormone therapy use, may be linked to better brain blood vessel health and fewer signs of damage as she ages..Sign up for our weekly HealthDay newsletter