A second pregnancy reshapes the maternal brain in ways that both resemble and differ from those seen during a first pregnancy, according to new research. Scientists found that while some pregnancy-related brain changes recur, subsequent pregnancies also produce unique adaptations that may help mothers meet the demands of caring for more than one child.
The study, published in Nature Communications, builds on earlier evidence showing that a first pregnancy reorganizes brain regions involved in social and emotional processing. Until now, researchers did not know whether later pregnancies simply reinforced these changes or produced additional patterns of brain plasticity.
How the Study Was Conducted
Researchers at Amsterdam UMC followed 110 women over time, including first-time mothers, women expecting a second child, and women who did not become pregnant. Participants underwent repeated magnetic resonance imaging (MRI) scans before, during, and after pregnancy, allowing the researchers to monitor changes in brain structure over time.
This longitudinal design enabled the team to distinguish pregnancy-related brain changes from those associated with normal aging. By comparing the different groups, the researchers identified which changes were unique to first pregnancies and which occurred during subsequent pregnancies.
Lead author Elseline Hoekzema, who heads the Pregnancy Brain Lab at Amsterdam UMC, said the findings provide the first clear evidence that brain plasticity continues during later pregnancies. According to the researchers, these adaptations may help support the cognitive and emotional demands associated with raising one or more children.
Different Brain Networks Adapt in Different Pregnancies
The researchers found that a first pregnancy produced the most substantial changes in the Default Mode Network, a group of interconnected brain regions involved in self-reflection, social cognition, and understanding the thoughts and emotions of others.
Although the Default Mode Network also changed during a second pregnancy, these changes were less pronounced. Instead, greater adaptations occurred in brain networks responsible for attention control and processing sensory information from the surrounding environment.
Researcher Milou Straathof, who led much of the data analysis, suggested that these changes in attention and sensory networks may help mothers manage the increased demands of caring for multiple children. Rather than simply repeating earlier adaptations, the brain appears to shift its plasticity toward functions that may become more important as family responsibilities expand.
Brain Changes Were Linked to Bonding and Depression Symptoms
The researchers also examined how pregnancy-related brain changes were associated with maternal behavior and mental health. They found a clear relationship between structural brain changes and the emotional bond between mother and infant, particularly following a first pregnancy.
Although this association remained detectable after a second pregnancy, it was less pronounced, suggesting that the initial transition to motherhood may involve more extensive brain reorganization than later pregnancies.
The study also identified links between changes in the brain’s cortex and symptoms of peripartum and postpartum depression. Among first-time mothers, these associations were strongest after childbirth, whereas among women experiencing a second pregnancy, they were more evident during pregnancy itself.
According to the researchers, this is the first study to demonstrate a direct relationship between pregnancy-related cortical remodeling and the risk of maternal depression. They suggest that these brain changes could eventually contribute to identifying women at greater risk for peripartum mood disorders earlier in pregnancy.
Implications for Maternal Health
The findings provide new insight into how the maternal brain adapts across multiple pregnancies and caregiving experiences. Because many women have more than one pregnancy, the researchers believe the study addresses an important gap in understanding women’s brain health.
Improved knowledge of maternal brain plasticity could eventually contribute to better screening, prevention, and treatment strategies for postpartum depression, which affects an estimated 10% to 15% of mothers worldwide. Understanding how brain changes differ between first and later pregnancies may also help clinicians determine when additional monitoring or support could be most beneficial.
The study also highlights the remarkable capacity of the adult brain to adapt in response to major life experiences. By demonstrating that pregnancy reshapes brain networks involved in emotion, social behavior, attention, and caregiving, the research reinforces the view that the human brain remains highly adaptable throughout the reproductive years.
Future research will be needed to determine how long these pregnancy-related brain changes persist, how they influence parenting over the long term, and whether similar patterns occur across different populations and healthcare settings. The findings nevertheless provide a more detailed understanding of motherhood as a powerful driver of long-term neurobiological change.