How pregnancy re-wires the brain to prime for motherhood

Pregnancy involves creating a new human brain entirely from scratch.

But it also has a significant impact on the brains of mothers, too, initiating a small “software update” to prepare them for motherhood.

That’s according to the largest study of its kind, where researchers found that pregnancy reduces the brain’s grey matter—the nerve-rich part of the brain that processes information, emotions, and empathy—by roughly 5% on average.

But before you panic: scientists say that’s likely the point.

Let’s break it down

Researchers scanned the brains of 127 women from before conception through six months postpartum, and compared them to scans from other women who’d never been pregnant.

• They discovered a ~5% average loss in grey matter for pregnant women, which partially returned six months after giving birth (but not fully).
  
• By contrast, the amount of gray matter in women who weren’t pregnant stayed consistently steady.
  

But…Rather than being a cause for concern, these changes appear beneficial when it comes to caring for newborns, researchers say.

• The greater the losses in brain matter, the more likely women were to say they were relating to, and bonding well with, their babies after birth.
• In short: pregnancy appears to “re-wire” the human brain to prime for motherhood.

Why it’s a big deal: Scientists are still mapping the intricacies of pregnancy, especially when it comes to changes in the brain. Better understanding that transformation will help doctors spot when something’s off, such as postpartum depression, instead of dismissing the symptoms as typical for pregnancy.