Pregnancy Changes Mothers' Brains. These Recent Discoveries Are Showing Us How

Aleksandar Nakic via Getty Images I’d looked in every drawer, through every basket and on every countertop. I’d emptied out the contents of my purse and searched my coat pockets. Nothing. My husband’s keys had disappeared. It wasn’t until I walked outside 30 minutes later that I found them, dangling from the lock on our front door. That sort of absent-mindedness was unusual for me—and incredibly frustrating. Since becoming pregnant with my first child in early 2024, my mind has felt different. I commonly lose my train of thought and grasp for words on the tip of my tongue. Deep, critical thinking can be exhausting.

None of this is unusual. Up to 80 percent of pregnant women report memory issues and, for many, those struggles continue into the early postpartum period. Often referred to as “mommy brain” or “baby brain,” these feelings of brain fog, forgetfulness and trouble concentrating are generally portrayed and experienced as deficits. But a body of recent research is revealing what actually happens inside women’s heads during this period: Their brains’ structures and functions are profoundly changing—and that remodeling, the studies suggest, is largely positive.

Throughout pregnancy, the body is flooded with hormones—namely, estrogen and progesterone—that support fetal development and create a stable environment for the baby. But these fluctuations, among other physiological shifts, also have implications for the mind. Mothers’ brains look different, and the changes facilitate their connection to and understanding of their infants.