What Happens to a Mother’s Brain During and After Pregnancy?
- Amy Simpson
- Jun 17
- 5 min read
Have you ever wondered why motherhood feels so intense—mentally, emotionally, even spiritually? The answer lies in your brain. Pregnancy and postpartum are periods of profound neurobiological change, as significant as adolescence. These changes are not just hormonal. They are structural, functional, and long-lasting.
Understanding what happens to your brain and body when you become a mother can help you make sense of how you're feeling—and why it's not all in your head.
Does Pregnancy Change the Brain?
Yes. Pregnancy literally reshapes the maternal brain. During pregnancy, there is a measurable reduction in grey matter volume in areas involved in empathy, social reasoning, and emotional regulation. This synaptic pruning is not a loss of function; it’s a neurological refinement that prepares you for responsive caregiving.
These structural changes were first highlighted in a 2017 study published in Nature Neuroscience, which found that they persist for at least two years postpartum. But far from being detrimental, this pruning sharpens a mother’s ability to read facial expressions, detect threats, and respond to her infant’s cues.
Later studies have shown that these brain areas regenerate after the early postpartum period, reflecting the plasticity of the maternal brain.
What Hormones Are Involved in Motherhood?
The endocrine system plays a major role in motherhood. The key players include:
Oestrogen: elevated during pregnancy, it supports uterine growth and blood flow, but drops sharply after birth.
Progesterone: also high in pregnancy, it promotes calmness.
Oxytocin: the “bonding hormone,” released during labour, skin-to-skin contact, and breastfeeding.
Prolactin: drives milk production and promotes maternal behaviours.
Cortisol: rises in late pregnancy and can temporarily blunt stress responses.
Dopamine: modulated by oestrogen and drops postpartum, which may influence mood and motivation.
Together, these hormones orchestrate physical and emotional changes designed to support maternal caregiving. Their influence is strongest in the first year but continues to ripple through the lifespan.
Why Do Mothers Feel Emotionally Different After Birth?
Motherhood activates and rewires brain circuits involved in reward, empathy, vigilance, and sensory processing. You may feel more attuned to your baby's needs, but also more sensitive to noise, interruption, and disconnection. These aren’t just psychological states, they’re neurochemical shifts.
After birth, many mothers experience a drop in oestrogen and dopamine, which can lead to mood fluctuations, anxiety, or emotional flatness. This is the brain recalibrating its baseline.
Oxytocin and prolactin play protective roles by fostering bonding and even making night waking feel more tolerable. But if breastfeeding is difficult or sleep deprivation is extreme, these systems may not offer the same buffering effects.
Is “Mum Brain” Real?
The short answer is yes, but not in the way it’s often portrayed. The foggy thinking, forgetfulness, and scattered attention that some mothers experience, particularly in the early weeks, are common. But these symptoms are not signs of damage or decline. Instead, they reflect brain systems under rapid renovation.
Recent research has found that motherhood is associated with enhanced long-term cognitive function, especially in women who have two to four children. The complexity of parenting may act as a cognitive exercise, what I'm now referring to as - “use it or lose it” (lol).
So, if you feel mentally slower in the short term, be reassured that your brain is adapting, not declining.
Can Motherhood be Compared to Adolescence?
Both matrescence (the transition to motherhood) and adolescence are periods of intense neuroplasticity. In both cases, the brain is reorganising itself in response to a new developmental role, whether it’s moving into adulthood or parenthood.
Like adolescence, matrescence brings:
Shifting identity
Emotional sensitivity
Risk of mood disorders
Heightened social awareness
Understanding that these changes are biologically normal, but not always easy, can help mothers feel validated and better supported.
Does the Brain Ever Go Back to Normal?
The maternal brain doesn’t “go back”—it evolves. The structural changes seen in pregnancy often begin to reverse after the first postpartum year, but many of the adaptations are lasting. They include:
Enhanced social cognition
Improved multitasking ability
Greater emotional depth
Stronger connection to meaning and purpose
These long-term changes are a biological investment in caregiving, attachment, and human survival.
The Impact of Perimenopause on the Maternal Brain
If you are becoming a mother in your mid-to-late 30s or early 40s, your brain may be undergoing two major transitions at once: matrescence and early perimenopause.
Early perimenopause (Stage -2 of the STRAW+10 framework) begins around age 40 and involves fluctuating oestrogen, disrupted sleep, and mood instability. These neurological changes can overlap with those of new motherhood, increasing the risk of:
Cognitive fatigue
Anxiety or panic
Sleep fragmentation
Hormonal sensitivity
Recognising that motherhood and perimenopause can collide is key to providing the right support, especially in women with underlying ADHD, depression, or hormonal sensitivity.
What Is the HPA Axis and Why Does It Matter for Mothers?
The hypothalamic-pituitary-adrenal (HPA) axis regulates your stress response. In early motherhood, this system becomes more sensitive, especially during sleep deprivation or emotional overload.
Your baby is also developing their own HPA axis, and in the early weeks, your systems are tightly connected. Through skin-to-skin contact, feeding, and co-regulation, your nervous systems literally sync.
This is why maternal mental health is so crucial, not just for you, but for your baby’s future resilience.
Final Thoughts: Yes, You Are Wired for This, But You Still Deserve Support
The neurobiology of motherhood is one of the most underappreciated areas of health science. It is not enough to say motherhood is “hard”we must acknowledge that it is a full-body neurological shift, with real implications for mood, memory, behaviour, and identity.
With awareness, education, and the right care, the changes in your brain and hormones can become a source of strength—not suffering.
Learn More About the Science of Motherhood
If you're curious about how your brain and body are changing during motherhood, or you’re looking for evidence-based support for your transition, get in touch for a free assessment.
Amy is a degree-qualified naturopath dedicated to helping busy, tired clients regain their energy and vitality.
She combines evidence-based naturopathic medicine, nutrition, and lifestyle interventions to empower clients on their journey to optimal health. Whether it’s reclaiming energy, balancing hormones, resolving digestive issues, or enhancing overall well-being and longevity, her personalised approach focuses on identifying and addressing the root cause of health concerns. With a Bachelor of Health Science, ongoing studies in a Master of Advanced Practice, and full membership in the Naturopaths and Herbalists Association of Australia, Amy offers a unique blend of traditional wisdom and science to support individuals and families at every stage of life.
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