A woman's uterus grows to over 500 times
its normal size during pregnancy.
But not all changes are visible.
In fact, some of the biggest changes happen in her brain.
When a mother sees her newborn for the first time,
it's love at first sight, literally.
That's because once she gives birth,
core regions of her brain's reward network kick in.
They signal the release of feel-good hormones
like dopamine and oxytocin into her blood,
which immediately triggers a strong connection
of love and devotion to her newborn.
In fact, studies show that recent mothers
have similar levels of oxytocin as romantic couples
who are newly in love.
And human moms aren't alone here.
Scientists discovered that rodents
got a bigger kick of dopamine from feeding their pups
than from receiving injections of cocaine.
What's more, brain scans reveal that a human mom
has a similar experience when she sees her infant smiling.
But it's a different story when her baby is crying.
Those cries activate a network in the mom's brain
known as the emotion regulation network.
It includes the prefrontal and cingulate control systems,
which help control her emotions.
And that's important since it can be easy to lose
your temper when you're running on very little sleep
and are distressed by the baby's cries.
And while motherhood can be exhausting,
new moms are actually more alert than normal
thanks to their brain's salience network.
Scientists think giving birth activates this network to help
a mother detect threats and protect her infant from harm,
especially in dangerous situations
when that network can help ramp up adrenaline.
But on a daily basis,
Mom needs to understand her newborn's needs.
To accomplish that, she uses empathy,
which comes from her brain's social network.
It involves the insular and amygdala,
which researchers found became more active
when moms looked at photos of their babies
in distress compared to neutral photos.
But it's not just the mom's brain that changes.
Research shows that a dad's brain releases oxytocin
when he interacts with his baby too.
This is often accompanied by a surge
of another hormone: prolactin.
It's often called the milk hormone because it triggers
the production of breast milk,
but men can produce it too,
and researchers have found that dads
who frequently played with their babies
had higher prolactin levels in their blood
than fathers who didn't.
They were also more responsive to their baby's cries.
So in the end, having a child is a big change.
Not just for your lifestyle, for your brain too.