Oral Contraceptive Use Linked to Brain Structural Changes

A recent study uncovered intriguing insights into the impact of oral contraceptives (OCs) and endogenous sex hormones on the brain's fear-processing regions. The findings were published in Frontiers in Endocrinology.

The study was conducted with the participation of healthy adults aged 23-35, focused on individuals who identified as women and fell into different contraceptive use categories. The groups included current OC users, past OC users, women who had never used hormonal contraception, and men. Researchers assessed endogenous sex hormones in saliva and ethinyl estradiol (EE) levels in current OC users. They employed advanced imaging techniques to analyze brain structures associated with fear processing.

When comparing the groups, researchers discovered a sex-related difference: all groups of women had larger gray matter volumes (GMVs) in the dorsal anterior cingulate cortex, a region implicated in fear promotion, compared to men. However, only current OC users exhibited thinner ventromedial prefrontal cortex, a region associated with fear inhibition. Intriguingly, women who had never used hormonal contraceptives had a thicker right anterior insular cortex, regardless of their menstrual cycle phase, compared to past OC users.