In 2016, for the first time ever, more American women had babies in their early 30s than in their 20s. Giving birth at any age comes with changes — to your body and bank account. But there are some key differences between giving birth in each decade. Giving birth changes a mother’s brain in many different ways. When she first sees her newborn, core regions of her brain’s reward network kick in, giving her an instant connection. Father’s also experience changes in their brain when they spend quality time with their babies.