Second pregnancy leaves a different mark on the brain
Amsterdam UMC researchers say brain scans show first and second pregnancies alter maternal brain networks in distinct patterns.
By Priya Raghavan · Science Reporter
3 min read
A second pregnancy changes the maternal brain in a pattern that differs from a first pregnancy, according to researchers at Amsterdam UMC. The findings, published in Nature Communications, may help scientists better understand maternal mental health problems, including peripartum depression.
The study extends earlier work by Elseline Hoekzema and colleagues showing that pregnancy can alter both the structure and function of the human brain. In the new research, the team tracked 110 women over time, including women pregnant with a first child, women pregnant with a second child and women who did not have children during the study period.
Amsterdam UMC said the researchers used repeated brain scans to follow changes across the study. The results showed that the brain changed during both first and second pregnancies, but the affected networks and the strength of the changes were not identical.
Different networks showed the largest shifts
According to the research team, first pregnancies were linked to the strongest changes in the brain’s Default Mode Network. That network is involved in functions such as self-reflection and social cognition.
During a second pregnancy, the Default Mode Network also changed, but less prominently, Amsterdam UMC reported. The most notable second-pregnancy changes appeared in networks tied to attention control and responses to sensory information.
Researcher Milou Straathof, who analyzed the data, said in Amsterdam UMC’s account of the study that the pattern seen in second pregnancies involved systems that help people react to sensory signals and direct attention. The researchers said those processes could be useful for mothers caring for more than one child.
Hoekzema, head of the Pregnancy Brain Lab at Amsterdam UMC, said the work shows that second pregnancies also reshape the brain. She said the findings indicate that each pregnancy has both shared and distinct effects on the maternal brain.
Links to bonding and depression
The researchers also examined whether pregnancy-related brain changes were associated with the mother-child bond. Amsterdam UMC said the connection between brain changes and bonding was stronger after a first pregnancy than after a second.
The study also found associations between changes in the brain’s structure and peripartum depression in both first and second pregnancies. Amsterdam UMC said the work provides the first evidence that pregnancy-related changes in the cortex are linked to maternal depression.
The timing of those associations differed by pregnancy history, according to the team. Among first-time mothers, the depression-related links were most visible after birth. Among women pregnant with a second child, the links were more apparent during pregnancy.
Amsterdam UMC said the findings could support better recognition and treatment of mental health problems in mothers. The researchers said understanding how the brain adapts to motherhood is an important step toward improving care, including efforts related to postpartum depression.
The paper, “The effects of a second pregnancy on women’s brain structure and function,” was written by M. Straathof, S. Halmans, P. J. W. Pouwels, E. A. Crone and E. Hoekzema. It appeared in Nature Communications in 2026.
This story draws on original reporting from ScienceDaily.