Exposure to Ovarian Hormones Linked to Larger Volumes in Brain Regions

WEDNESDAY, July 1, 2026 (HealthDay News) — Endogenous and exogenous lifetime exposure to ovarian hormones is associated with structural brain measures consistent with preserved brain aging, according to a study published July 1 in NeuroImage.

Robyn A. Honea, Ph.D., from the University of Kansas Alzheimer”s Disease Research Center in Fairway, and colleagues analyzed baseline data from 459 women aged 65 to 80 years enrolled in a 12-month randomized aerobic exercise study. Retrospective self-report of hormonal birth control and menopausal hormone therapy (MHT) use were examined in relation to structural magnetic resonance imaging metrics for gray matter volume and cortical thickness.

The researchers found that birth control use versus no use was associated with greater gray matter volume in temporal, occipital, and frontal regions in older adulthood. There was a link for longer birth control duration with larger fusiform gyrus volume. Compared with no use, combined birth control and MHT use was associated with greater volume in parietal and temporal areas and thicker cortex in the posterior cingulate and temporal gyri. There was a correlation between later menopause onset with greater posterior cortical thickness. There were no associations for MHT timing or birth control start age.

“Estrogen is neuroprotective,” co-lead author Amber Watts, Ph.D., also from the University of Kansas Alzheimer”s Disease Research Center, said in a statement. “It”s beneficial for white matter integrity. It helps protect neurons and strengthens neural connections. It is also important for vascular function. One of the things we get wrong about estrogen is people think of estrogen as this thing that has to do with reproduction. But really, estrogen is very important for a lot of different body systems.”

Abstract/Full Text