We’ve probably all come across the terms “pregnancy brain” or “mommy brain.”
But: based on the latest research, perhaps such expressions need to be revised! Instead, let’s delve into the positive changes that happen to a person’s brain when they become a parent.
Today, we talk about this topic with Evita Varela, the “Neuroscientist Doula.” With a background in neuroscience, Evita knows a lot about the changes happening to the brain during pregnancy and the postpartum period.
Evita herself has experienced a positive change in her cognition and in how she relates to people ever since becoming a mom in 2016, and she also very often sees these positive changes in her clients. Follow Evita on Instagram for her insights into pregnancy, birth, motherhood, woman power and personal development.
It is said that pregnant people often feel forgetful or frazzled (therefore the term “pregnancy brain”) – why is this and how can these changes be described?
My view on this is that there are a lot of unknown topics and procedures that women have to tackle during pregnancy. So there is a subjective feeling that they are doing less well on what they were used to doing or that they are more distracted and forgetful.
Early studies of cognition testing pregnant women simply asked them to describe their cognitive experience during pregnancy. Despite their subjective reports of cognitive decline, there is only one meta-analysis of 20 studies reporting a statistically significant but tiny decline in memory performance for women, largely confined to the third trimester of pregnancy.
Importantly, pregnancy impacted only the subset of cognitive skills that place high demands on effortful processing (behavioral inhibition, selective attention and cognitive inhibition, working memory, and cognitive flexibility).
There are many other studies conducted in many countries that find no objective memory changes during pregnancy or postpartum, even for those mothers who self-report ‘baby brain’.
Can you point us to some of the latest research?
More recently, the cognitive tests have evolved into more precise batteries that encompass many facets of cognition.
When it comes to attention, planning and problem-solving, no differences are detected between pregnant and non-pregnant women.
And now the plot twist: in a study where women were shown ‘baby items’ versus ‘adult items’ photographed against various landscapes, pregnant women showed enhanced long-term memory and enhanced associations between objects, which are processes involving the hippocampus.
So we’re thankfully in an era when we’re rethinking the ‘baby brain’ as being about cognitive reorganization rather than straight memory decline.
That’s very interesting! Can you explain some more the changes that happen in pregnancy and how long they last for?
The biggest brain changes in pregnancy happen during the third trimester and happen primarily thanks to the hormone oestradiol.
Pregnancy-induced brain plasticity sculpts brain networks involved in the sense of self, maternal caregiving, reward and motivation, threat detection, emotional regulation and social cognition.
A mother’s abilities to empathize with and decode their baby’s needs, to bond and to attach to their baby are highly enhanced. The changes are both structural (gray matter loss, but enhanced connectivity) and functional (level of neural network activity or network connectivity).
It is impressive that the greater the gray-matter volume reduction, the greater the intensity of neural activity when mothers see their baby’s photo or listen to their baby’s cry. So gray matter volume loss and neural activity level predict maternal attachment.
These brain changes that start in pregnancy persist, even years after birth.
How are fathers and partners affected by this phenomenon?
Some brain circuitry (particularly within subcortical structures such as the hippocampus, amygdala, and nucleus accumbens) is changing for fathers/partners as well and it is proportional to the time they spend with the baby.
In a recent study, fathers who reported stronger prenatal bonding with the unborn infant, and planned to take more time off from work after birth, subsequently showed larger cortical volume decreases.
Larger reductions in gray matter volume also emerged among fathers who reported stronger postpartum bonding with the infant, lower parenting stress, and more time spent with their infant.
As far as hormones go, fathers’ concentrations of oxytocin significantly differ from those of nonfathers. Moreover, fathers exhibit similar oxytocin levels as mothers.
Interestingly, fathers-to-be do not differ from non-expecting men in oxytocin levels. So, the role of oxytocin regulation in men seems more relevant after the infant’s birth, rather than already during pregnancy as previously reported for women.
Also, fathers display increased levels of prolactin that correlates to prolactin levels of their partners and begin to rise already from the third trimester of their partner’s pregnancy.
I understand that the brain changes during pregnancy and postpartum are positive. How is this going along with the rise in anxiety and mental health issues we may see postpartum?
The transition to motherhood is a big rite of passage with many layers. There is a huge hormonal shift, changes in everyday life and a deep identity shift.
Medical Anthropologist Dana Raphael (who coined the term doula and advocated for women to receive doula care), coined the term ‘matrescence’ in the beginning of the 70s to describe how the mother is born as the baby is born.
The ‘feel-good’ hormones estrogen and progesterone that rise high during pregnancy (as they are largely produced by the placenta) plummet right after birth. This hormonal shift brings the so-called baby blues.
The new mother has the need of deep nourishment with warm, nutritious foods, rest, therapeutic/loving touch, input from wise women in her community and contact with nature (see Ref.3). If her needs are not fulfilled, this can manifest as deep blues and anxiety.
See also our article “Postpartum Depression: How to Know if it's More than Baby Blues?”
Anything else you would like to share?
I am delighted that there is a lot of interest around brain changes during pregnancy and matrescence during the last years (see References 1,2,6,7,8 for the scientific publications).
For readers who wish to go deeper in the subject, I recommend the book “Baby brain” by Dr. Sarah Mckay.
Thanks Evita!
References:
Pregnancy leads to long-lasting changes in human brain structure (Hoekzema et al., Nat.Neurosc. 2017) https://www.nature.com/articles/nn.4458
Neuroanatomical changes observed over the course of a human pregnancy Pritschet et al., Nat.Neurosc. 2024) https://www.nature.com/articles/s41593-024-01741-0
The fourth trimester, Kimberly Ann Johnson, Shambala Boulder 2017
Baby brain, Dr Sarah Mckay, Hachette Australia 2023
Article of UC Santa Barbara on latest maternal brain research
The Paternal Brain in Action: A Review of Human Fathers’ fMRI Brain Responses to Child-Related Stimuli ( Provenzi et al., Brain Sciences 2021)
Cortical volume reductions in men transitioning to first-time fatherhood reflect both parenting engagement and mental health risk (Saxbe and Martínez-García, Cereb. Cortex 2024)
A systematic review of human paternal oxytocin: Insights into the methodology and what we know so far (Grumi et al., Dev Psychobiol. 2021)
