Growing a human being is no small feat1
-- just ask any newly pregnant woman. Her hormones2
surge as her body undergoes a massive physical transformation3
, and the changes don't end there. A study published Monday in Nature Neuroscience reveals that during pregnancy4
women undergo significant brain remodeling that persists for at least two years after birth. The study also offers preliminary evidence that this remodeling may play a role in helping5
women transition into motherhood.
A research team at Autonomous6
University of Barcelona, led by neuroscientist Elseline Hoekzema of Leiden University, performed brain scans on first-time mothers before and after pregnancy and found significant gray matter changes in brain regions associated with social cognition and theory of mind -- the same regions that were activated7
when women looked at photos of their infants. These changes, which were still present two years after birth, predicted women's scores on a test of maternal8 attachment9
, and were so clear that a computer algorithm could use them to identify which women had been pregnant.
One of the hallmarks of pregnancy is an enormous increase in sex steroid hormones such as progesterone and estrogen, which help a woman's body prepare for carrying a child. There is only one other time when our bodies produce similarly large quantities of these hormones: puberty. Previous research has shown that during puberty these hormones cause dramatic structural10
and organizational changes in the brain. Throughout adolescence11
both boys and girls lose gray matter as the brain connections they don't need are pruned12
, and their brains are sculpted13
into their adult form. Very little research has focused on anatomical brain changes during pregnancy, however. "Most women undergo pregnancy at some point in their lives," Hoekzema says, "But we have no idea what happens in the brain."