There's been plenty of research done on how women's brains change before and after pregnancy, but much less on how the brain changes during pregnancy. Now a new study published in the journal Nature Neuroscience is giving researchers more insight into the unique neurological changes that happen between conception and birth.
Liz Chrastil, a neuroscientist at UC Irvine, opted to have her brain scanned every few weeks during her entire pregnancy to see what changes occur. It’s the closest look yet and researchers call the data astounding.
Why research this now?
You may think it’s not safe to scan pregnant women — but that’s not the case, according to Emily Jacobs, senior study author and associate professor of psychological and brain sciences at UC Santa Barbara.
"Think about it, we have beautiful maps of the fetal brain going up to about 20 weeks gestation, and that requires an MRI scan,” said Jacobs during a conversation on AirTalk, LAist's daily news program which airs on 89.3 FM. "Scientists just didn't bother to move the bore of the MRI scanner down two feet to see what was happening to mom's brain.”
What did scientists find about brain change?
Researchers scanned Professor Chrastil’s brain every few weeks, from preconception through two years postpartum. They say they found the brain undergoes a "choreographed change" during gestation, and that it loses volume. The research also found changes that persisted even two years after birth.
“[It's] not unlike the cortical thinning that happens during puberty in all sexes," said Jacobs. "And in both cases, we think that this adaptive process enables the brain to become more specialized."
The maternal brain undergoes this choreographed change across gestation.
Jacobs said it’s pretty clear how these changes impact behaviors in animals. For example, in rodents, the surge in progesterone — a hormone that prepares the uterus for pregnancy — rewires brain circuits and enhances a mother’s sensitivity to smells and sounds, which triggers behaviors like nest building, licking and grooming.
It’s a lot more complicated in humans though.
“Parental behavior occurs all the time in non-gestational mothers, adoptive parents, grandparents, fathers, people who don't experience gestation firsthand, but still display all of the nurturing behaviors that we need to care for children,” Jacobs said. “So it could be that this is one way of getting that fine tuning of the brain, but there's probably a whole bunch of other ways that don't require gestation.”
The beauty of a changing brain
Brain matter loss and thinning certainly doesn’t sound like a good thing. Most of us have likely heard of “mommy brain,” a phenomenon of early parenthood marked by brain fog and memory loss. So does pregnancy leave lasting scars on the brain?
While we need more research, Jacobs says new data coming out suggests women who’ve been pregnant have younger looking brains later in life compared to their counterparts.
“The analogy I always give is thinking about Michelangelo's David, right? So the artist starts off with this block of marble, and the underlying beauty is revealed through the art of removal," Jacobs said.
What now?
Jodi Paluwski, a neuroscientist and author of Mommy Brain: Discover the amazing power of the maternal brain, said we need more research to investigate how different factors affect biological changes and use it to promote brain health.
“I think we need to move forward with greater support for parents, for mothers, so that they can remain healthy during this time and their brain can do what it's meant to do,” Paluwski said.
