U.S, Feb. 20 -- In an earlier study, Elseline Hoekzema and her team showed for the first time that pregnancy can change the structure and function of the human brain. In this new study, researchers at Amsterdam UMC followed 110 women to see how the first and second pregnancies bring different changes to mothers' brains.

Of the total participants, some became mothers for the first time, some had their second child, and others did not have children. By using repeated brain scans, the researchers were able to see exactly how the brain changed.

Published in Nature Communications, the study found that during the first pregnancy, the biggest changes happened in the brain's "default mode network." This area helps with thinking about oneself an...