11 fascinating studies that reveal how motherhood shapes minds, bodies, and brains

From structural changes in the brain to shifts in stress hormones and the invisible burden of “mental load,” research continues to uncover the profound biological and psychological effects of motherhood. These 11 studies explore how maternal behaviors, biology, and experiences shape not just their children’s development, but also mothers’ own mental and physical well-being.

1. Supportive mothers may boost children’s intelligence through age 10

A large longitudinal study published in Intelligence found that maternal supportiveness—defined by behaviors like sensitivity, cognitive stimulation, and positive regard—was associated with higher general intelligence in children, lasting into late childhood. Using observational assessments from when the children were 14 to 36 months old, researchers found that children with more supportive mothers tended to score higher on cognitive tests well into their elementary school years.

The relationship between maternal supportiveness and child intelligence remained significant even after accounting for the mother’s own cognitive abilities and the child’s temperament. While these early advantages may fade as genetic influences become more dominant in adulthood, researchers suggest that a small cognitive edge during key developmental years may have lasting life implications, such as better academic opportunities or higher self-confidence. The study highlights how maternal warmth and intellectual engagement during play may foster broader cognitive development.

2. Motherhood is linked to long-lasting changes in brain structure

According to a study in Scientific Reports, mothers exhibit higher gray matter density across various brain regions compared to women who have never given birth. These structural differences, found even decades after childbirth, suggest that the experience of pregnancy and early caregiving may have enduring effects on the brain’s architecture.

The areas of increased gray matter in mothers were widespread, spanning both cognitive and emotional processing regions. Notably, these changes were not observed in fathers, pointing to pregnancy-related biological mechanisms as the likely cause. Though the structural changes weren’t directly linked to well-being, they may offer protective effects against aging. This research adds to growing evidence that motherhood reshapes the brain, not just in the short term, but across the lifespan.

3. A mother’s touch fosters emotional, cognitive, and social development

Skin-to-skin contact and affectionate touch are more than just comforting—they have measurable benefits for babies’ health and development, as well as for mothers’ mental well-being. Research reviews have found that newborns who experience more parental touch exhibit better temperature regulation, sleep, feeding, and brain development. These benefits extend to premature infants, with studies showing lower mortality, better weight gain, and reduced stress when mothers practice kangaroo care.

Touch benefits mothers as well. Daily skin-to-skin contact has been shown to reduce symptoms of postpartum depression and anxiety. Long-term studies suggest that early maternal touch improves mother-child emotional attunement and communication even years later. Despite outdated beliefs discouraging affectionate parenting, the science is clear: regular, nurturing touch is vital for both infant and maternal health.

4. Stress hormones may alter maternal brain responses and caregiving

A study in Psychoneuroendocrinology uncovered how maternal stress, measured through the hormone cortisol, is linked to less sensitive and more intrusive parenting behaviors. First-time mothers with higher cortisol levels showed reduced brain activity in regions responsible for emotion regulation and auditory processing when hearing their baby cry. These same mothers also tended to interrupt or control their infant’s play more frequently.

The findings suggest that elevated stress may interfere with the brain’s ability to tune into a baby’s needs, potentially disrupting the parent-infant bond. The study emphasizes the importance of maternal well-being in the postpartum period, not only for mothers’ mental health but also for fostering responsive caregiving. It points to stress as a key biological factor that may shape parenting behavior at the neurological level.

5. Romantic love may be rooted in mother-infant bonding systems

An evolutionary theory proposed in Frontiers in Psychology suggests that romantic love may have developed from the same biological systems that support mother-infant bonding. Both experiences involve deep emotional connections, physical closeness, and a desire to protect and nurture the loved one. The theory is backed by neuroimaging studies showing that similar brain regions—particularly those rich in oxytocin and dopamine receptors—are active in both maternal and romantic love.

These shared pathways include areas associated with reward, motivation, and attachment. Hormonal overlaps, especially in oxytocin levels, further support the idea that the intense emotional drive seen in new mothers may have been evolutionarily adapted to foster long-term romantic bonds. This theory reframes romantic attachment as a byproduct of maternal bonding mechanisms, underlining how central motherhood is to human social behavior.

6. Mothers are more motivated to win rewards for their children than for themselves

In a study published in Social Cognitive and Affective Neuroscience, researchers found that mothers responded more quickly and showed stronger brain activity when playing games to win prizes for their children than when playing for themselves. Despite receiving no additional benefits, mothers exerted more effort and experienced more neural reward response when their children stood to gain.

This finding challenges the “self-advantage” principle in reward processing, where people typically show stronger reactions to personal rewards. The heightened motivation and neural engagement observed in mothers suggest that caring for one’s child can override self-interest at the biological level. It offers insight into the deeply ingrained, perhaps evolutionarily wired, prioritization of children’s well-being in maternal brains.

7. The invisible mental burden of motherhood affects well-being

While mothers often perform more physical chores, a study in the Archives of Women’s Mental Health found that they also carry a much heavier share of the cognitive load—planning, organizing, and anticipating household tasks. This form of “invisible labor” was linked to higher levels of depression, stress, and burnout in mothers of young children.

Even when physical tasks were somewhat shared with partners, the unequal division of mental labor had a stronger impact on maternal well-being. The findings shed light on why many mothers feel overwhelmed even when partners appear involved. Addressing this mental load—often unacknowledged—may be key to improving maternal mental health and relationship satisfaction.

8. Gut bacteria in pregnant mothers may support fetal brain development

A mouse study published in Molecular Metabolism found that a specific gut bacterium, Bifidobacterium breve, enhanced fetal brain development when present in pregnant mothers. Fetuses exposed to the bacterium through their mothers had better nutrient transport and more active brain metabolism, including increased expression of proteins important for neuron growth and connectivity.

The research suggests that maternal gut health could influence how the fetal brain develops, offering a new potential pathway for non-invasive support during pregnancy. While more research is needed in humans, the study highlights the far-reaching influence of maternal biology on offspring brain outcomes—even through the microbiome.

9. Maternal brain structure changes across pregnancy and postpartum

In the largest longitudinal brain imaging study of mothers to date, researchers found that first-time mothers experienced reductions in brain volume and cortical thickness during pregnancy, followed by increases in the postpartum period. These dynamic changes, published in Nature Neuroscience, affected areas related to emotion, attention, and social cognition.

The changes appeared to help mothers adapt to the demands of caregiving, with brain areas involved in maternal sensitivity and attachment undergoing the most transformation. The study supports the idea that pregnancy triggers a period of heightened brain plasticity in mothers—a biological remodeling that may prepare the brain for parenting while also influencing long-term maternal mental health.

10: Sensitive mothers shape how babies’ brains respond to happiness

A study in Developmental Science found that infants whose mothers were more sensitive during play showed greater brain activity in response to happy faces. The activation occurred in the dorsolateral prefrontal cortex, a region involved in emotion regulation and social cognition. This suggests that early maternal sensitivity may fine-tune the baby’s social brain toward recognizing and responding to positive emotional cues.

Interestingly, this effect was specific to happy faces, with no significant brain changes for fearful or angry expressions. The research highlights how positive maternal interactions in early life don’t just protect against harm—they actively promote emotional resilience and social development in infants.

11. Maternal warmth shapes personality development into adulthood

A study in American Psychologist found that children who received more affection from their mothers grew into more open, conscientious, and agreeable young adults. Using data from over 1,000 twins in the UK, researchers showed that these effects held even when controlling for genetics and shared environment by comparing identical twins raised in the same household.

Twins who received more maternal warmth at ages 5 and 10 were more likely to display personality traits linked to better life outcomes at age 18. These findings suggest that parenting—particularly affectionate and supportive maternal behavior—can have a lasting influence on personality. Importantly, the emotional tone of parenting, not just the absence of harm, matters in shaping who we become.