The Mysteries of the Maternal Mind: How Pregnancy Rewires the Brain for Parenthood
Pregnancy changes everything: body, belly, breasts, brain, and behaviour.
Please note: The terms “maternal,” “mother,” “women,” and “motherhood” were used in the original review article “The transition to motherhood: linking hormones, brain, and behavior,” which presented the findings about changes in the brain during pregnancy and after childbirth. The following article's author, Katja Holzhei, acknowledges all pregnant people, regardless of their gender identity.
Pregnancy: Everything Changes
Pregnancy is a time of transformation. We witness the body's visible changes—the growing belly and breasts, weight gain, a shifting centre of gravity, and altered posture. The physical adaptations are apparent to the eye, but pregnancy's profound and fascinating evolution extends far beyond the surface.
In Antoine de Saint-Exupéry's iconic tale, “The Little Prince,” the wise fox shared a timeless message with the young prince:
“What truly matters cannot be seen; it resides within the heart.” Very romantic. But, sorry, dear passionate reader, this is not adaptable to pregnancy. In this blog post, we look into the brain and how its hidden world of neurons and networks impacts one's journey to parenthood.
Body, Belly, Breasts, and … Brain
The research that inspired this blog post was published in August 2023. Scientists from the Universitat Autònoma de Barcelona (UAB), the Gregorio Marañón Health Research Institute, and the Hospital del Mar Research Institute have released an article that reviews existing studies about how women's brains change during pregnancy and after giving birth. They looked at how hormones, brain structure, and behaviour are connected. And they also provided a plan for future research in this area.
So, let’s see what we know about the very architecture of the brain during pregnancy and what needs more research, with brain science still in the early stages.
A Complex Connection: Brain Structure, Hormones, and Behaviour
We knew before that pregnancy is a journey of hormonal rollercoaster rides. Neurons rearrange, and the roots for parental affection start to develop. Growing evidence in the last decade has suggested already that pregnancy may significantly impact the maternal brain, causing long-lasting changes in its structure. Most studies conducted up to date, though, have used rats.
“There are coincidences between humans and other animals, but there are many cerebral differences, (...), and hormonal differences, (...)”, explains Camila Servin, a researcher from the UAB Department of Psychiatry and Legal Medicine and at the Hospital del Mar Research Institute. That is why the researchers emphasized the importance of developing research studies on females focused on the experience of pregnancy and childbirth.
The study looked into three key areas, trying to understand the connection between them:
alterations in the brain structure,
hormonal changes, and
maternal behavior.
The key findings identify crucial factors and knowledge gaps in understanding how humans adapt to (first-time) motherhood:
Fluctuating hormones trigger brain changes (plasticity processes).
Further research is needed to clarify the specific plasticity processes.
The human birth-giver-baby bonding experience remains unexplored.
Estrogen: The Brain Changer
The research believes that fluctuations of estrogens (specifically, oestradiol) are responsible for triggering alterations and driving brain plasticity during pregnancy and postpartum. Brain plasticity, or neuroplasticity, refers to the brain's ability to change and adapt throughout a person's life.
During different stages of pregnancy and post-birth, the amount of grey matter in the brain of the childbearing person varies. These structural changes, namely reduced grey matter in areas linked to social interactions and relations, can last at least for two years after giving birth.
Unique: The Human Baby-Bonding Experience
An area that we're not very knowledgeable about yet is how exactly the birth giver and their baby bond. The emotional and mental processes involved in building the relationship during pregnancy and postpartum are still among the least explored aspects of human parenthood.
Research has found that the changes in thoughts and feelings required for the bond set humans apart from other animals. But further studies must uncover these changes' precise mechanisms and details to deepen our understanding.
In Summary: The Known and the Unknown
What we know:
Brain plasticity, or neuroplasticity, refers to the brain's ability to change and adapt throughout a person's life.
There are two primary brain plasticity types: Structural and functional plasticity.
Pregnancy and the postpartum time change the brain of the birth giver.
During pregnancy, the type of brain plasticity that is most relevant is structural plasticity. This refers to physical changes in the brain's structure, including the formation of new neurons and the creation of new synaptic connections between neurons.
Research suggests that pregnancy can lead to changes in the brain's grey matter, including reductions in specific areas related to social interactions.
These changes can last for at least two years after giving birth.
Estrogens are the main hormones suspected to trigger these changes.
What we don’t know (yet):
We need more research to understand the changes in brain cell function, structure, and connections during the human transition to parenthood and how these changes impact a birth giver’s behaviour.
Sources:
