Nature Neuroscience | Volume 27 | November 2024 | 2253–2260
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Resource https://doi.org/10.1038/s41593-024-01741-0
the offspring12. Human studies have revealed GMV reductions in areas 
of the brain important for social cognition and the magnitude of these 
changes corresponds with increased parental attachment 13. Deeper 
examination of cellular and systems-level mechanisms will improve 
our understanding of how pregnancy remodels specific circuits to 
promote maternal behavior.
Although studied to a lesser degree, ties between maternal 
behavior and white matter microstructure (particularly connectiv -
ity between temporal and occipital lobes) have been noted31. Here we 
reveal pronounced GMV changes in regions within sensory, attention 
and default mode networks over the gestational window. In paral -
lel, we observed increased anisotropy in white matter tracts that 
facilitate communication between emotional and visual processing 
hubs37–39, including the inferior longitudinal fasciculus and inferior 
fronto-occipital fasciculus. Pinpointing the synchrony of gray and 
white matter changes that unfold in the maternal brain could be 
key to understanding the behavioral adaptions that emerge during 
and after pregnancy, such as honing the brain’s visual and auditory 
responses to infant cues and eliciting maternal behavior. Research 
into other major transition periods supports this idea. For instance, 
adolescence is a dynamic period characterized by region-specific, 
nonlinear decreases in GMV and increases in WMV, maturational 
brain changes that are tied to gains in executive function and social 
cognition40. For both adolescence 41 and matrescence, the consider-
able rise in steroid hormone production appears to remodel the brain 
(see ref. 25 for comparative analysis), promoting a suite of behaviors 
adaptive to that life stage. How specific neural changes give rise to 
specific behavioral adaptations has yet to be fully explored with 
respect to human pregnancy.
This precision imaging study mapped neuroanatomical changes 
across pregnancy in a single individual, precluding our ability to gen-
eralize to the broader population. T o benchmark our findings, we com-
pared the magnitude of GMV changes observed throughout pregnancy 
against data from nonpregnant individuals sampled over a similar time 
course. Doing so provided compelling evidence that pregnancy-related 
neuroanatomical shifts far exceed normative day-to-day brain variabil-
ity and measurement error. Evidence suggests that white matter micro-
structure remains fairly stable over a six-month period 42, but more 
studies are needed to compare the degree of white matter changes 
observed during pregnancy to normative change over time. Further, 
sampling larger cohorts of women will generate much-needed norma-
tive models of brain change (akin to ref. 43) throughout pregnancy to 
establish what constitutes a typical degree of neuroanatomical change 
expected during gestation and postpartum recovery.
These findings provide a critical rationale for conducting further 
precision imaging studies of pregnancy in demographically enriched 
cohorts to determine the universality and idiosyncrasy of these adap-
tations and their role in maternal health. Are the changes observed in 
our participant reflective of the broader population? Do deviations 
from the norm lead to maladaptive outcomes? A precision imaging 
approach can help determine whether the pace of pregnancy-induced 
neuroanatomical changes drives divergent brain health outcomes in 
women, as may be the case during other rapid periods of brain devel-
opment44. One in five women experiences perinatal depression45 and 
while the first FDA-approved treatment is now available46, early detec-
tion remains elusive. Precision imaging studies could offer clues about 
an individual’s risk for or resilience to depression before symptom 
onset, helping clinicians better determine when and how to intervene.