Summary: It is well-established that a woman’s first pregnancy causes significant structural changes in the brain, but new research reveals that the brain continues to evolve with a second child.
The study tracked 110 women through multiple pregnancies, finding that while the first pregnancy primarily reshapes the Default Mode Network (involved in self-reflection and social bonding), a second pregnancy focuses on networks related to attention and sensory response.
These unique adaptations likely prepare mothers for the complex cognitive demands of caring for multiple children at once, proving the maternal brain remains remarkably flexible throughout different stages of motherhood.
Key Facts
- Network Shift: First pregnancies impact the Default Mode Network (social processing), while second pregnancies more strongly alter networks involved in directing attention and reacting to stimuli.
- The “Multi-Tasking” Adaptation: Researchers believe the sensory and attention-based changes in second-time mothers are biological tools designed to help manage the needs of more than one child.
- Depression Link: For the first time, researchers linked cortical changes during pregnancy to peripartum depression. In first-time mothers, this was most visible after birth; in second-time mothers, it was more apparent during pregnancy.
- Mother-Child Bonding: The study found that while brain changes correlate with the mother-child bond, this link is more prominent during the first pregnancy than the second.
- Brain Plasticity: The findings underscore the extreme plasticity of the female brain, showing it can continually adapt and reorganize itself in response to major life events like subsequent pregnancies.
Source: Amsterdam UMC
Researchers at Amsterdam UMC have discovered that a second pregnancy alters the female brain.
Previous research from the same group had already demonstrated the impact of a first pregnancy on the female brain.
These results are published today in Nature Communications.
The research demonstrates that both a first and a second pregnancy have a strong and unique impact on mothers’ brains.
A previous study by Elseline Hoekzema and colleagues was the first to show that pregnancy changes the structure of the human brain. The research group also discovered that pregnancy changes brain functioning.
For this follow-up study, they tracked 110 women: some became mothers for the first time, others had their second child, and a third group remained childless. Repeated brain scans allowed them to see exactly what changed in the brain.
“With this, we have shown for the first time that the brain not only changes during the first pregnancy, but also during a second,” says Hoekzema, head of the Pregnancy Brain Lab at Amsterdam UMC.
“During a first and second pregnancy, the brain changes in both similar and unique ways. Each pregnancy leaves a unique mark on the female brain.”
Different brain networks change
The greatest changes during a first pregnancy occurred in the structure and activity of the so-called Default Mode Network. This part of the brain is important for many functions including self-reflection and social processes. During a second pregnancy, this network changed again, but less strongly.
However, during a second pregnancy, there were more changes in brain networks related to directing attention and responding to stimuli.
“It appears that during a second pregnancy, the brain is more strongly altered in networks involved in reacting to sensory cues and in controlling your attention”, explains researcher Milou Straathof, who analyzed the data. “These processes may be beneficial when caring for multiple children.”
Relationship with mother-child bond and maternal mental health
The researchers also found a link between changes in the brain and the bond between mother and child. This link was more prominent during a first pregnancy than during a second.
In addition, the researchers observed connections between structural brain changes and peripartum depression, both during a first and a second pregnancy, providing the first evidence that the changes taking place in a woman’s cortex during pregnancy relate to maternal depression.
For women who became mothers for the first time, this was especially visible after childbirth. For women having their second child, this was particularly the case during their pregnancy.
“This knowledge can help to better understand and recognize mental health problems in mothers. It is important that we understand how the brain adapts to motherhood.”
Importance of research into the maternal brain
This research provides new insights into how the female brain adapts to motherhood. The large majority of women become pregnant once or multiple times in their lives, yet we are only now starting to unravel how this impacts a woman’s brain.
This study contributes to addressing this important gap in knowledge on women’s biology. The results can also contribute to better care for mothers, for example in preventing and treating postpartum depression.
The findings also show that the brain is flexible and can continually adapt to major changes in a woman’s life.
Key Questions Answered:
A: “Normal” simply changes. These structural shifts aren’t temporary damage; they are functional refinements. Your brain is essentially upgrading its “software” to handle the social and sensory demands of parenting.
A: Your brain is actually focusing on different skills. While the first time was about forming a social identity as a “mother,” the second time around, your brain prioritizes the ability to split attention and respond quickly to multiple sensory cues—perfect for keeping an eye on a toddler while feeding a newborn.
A: This research provides the first evidence that specific cortical changes are linked to maternal depression. Understanding these “neural markers” could eventually help doctors identify which mothers are at higher risk and provide support earlier in the process.
Editorial Notes:
- This article was edited by a Neuroscience News editor.
- Journal paper reviewed in full.
- Additional context added by our staff.
About this pregnancy and neuroplasticity research news
Author: Jack Cairns
Source: Amsterdam UMC
Contact: Jack Cairns – Amsterdam UMC
Image: The image is credited to Neuroscience News
Original Research: Open access.
“The effects of a second pregnancy on women’s brain structure and function” by M. Straathof, S. Halmans, P. J. W. Pouwels, E. A. Crone & E. Hoekzema. Nature Communications
DOI:10.1038/s41467-026-69370-8
Abstract
The effects of a second pregnancy on women’s brain structure and function
While we have previously shown that a first pregnancy changes women’s brain structure and resting-state brain activity, it is currently unknown how a woman’s brain is transformed when she undergoes another pregnancy. Therefore, we performed a prospective pre-conception cohort study involving 110 women, including women who became pregnant of their second (PRG2) or first child (PRG1) and nulliparous women.
Multimodal MRI data were acquired and differential changes between PRG2 and PRG1 were observed in grey matter volume, white matter tracts and functional neural network organization.
Together, these results show similar but less pronounced structural and functional changes in the default mode and frontoparietal network in PRG2, suggesting a primary adaptation of these networks in first-time mothers that is further fine-tuned across a second pregnancy.
Furthermore, stronger alterations were found in PRG2 in the dorsal attention and somatomotor network including the corticospinal tract, pointing to an enhanced plasticity within these externally-oriented networks. Neurostructural changes in both groups related to mother-infant attachment and peripartum depression.
These findings show that a second pregnancy uniquely changes a woman’s brain, entailing both convergent and distinct neural transformations.
