How a woman’s brain changes during pregnancy

Question: I am in the 5th month of my first pregnancy and, in addition to being very happy, I notice some changes in my way of being, such as, for example, being more distracted and forgetful in my work. Is it normal? What produces it? (Maggie Bianchi, from Rosario)

During pregnancy, women’s brains undergo a series of profound changes that go beyond known hormonal adjustments. These changes are designed to prepare expectant mothers for the demands that motherhood brings.

One of the most notable findings (Nature Neuroscience9-16-24) is the reduction in the volume of the gray matter by up to 7% in certain areas, which persists up to two years after childbirth.

Although the reduction in volume may seem negative, this process of brain “thinning” or neuronal pruning reorganizes neuronal connections, helping mothers be more efficient in interpreting their baby’s needsin its empathy, social understanding and recognition of emotions that are key so that the mother can interpret and respond to her baby’s signals quickly and effectively.

The size returns to normal 6 months after delivery.

For its part, the white matter (made up of the bundles of nerve fibers that run through the brain and help neurons communicate with each other) grows more strongly, reaching its maximum in the second trimester and reducing almost to normal at the time. of birth.

In addition to changes in brain structure, during pregnancy there is also an increase in the production of oxytocin, known as the “love hormone,” which plays a crucial role in establishing maternal bonding.

Oxytocin levels increase during pregnancy and childbirth, facilitating the emotional connection between mother and baby. This increase also reduces stress and anxiety in the mother, helping to better cope with the challenges of early motherhood.

Another important change is the increased activation of the brain’s amygdala, a structure involved in emotional response and fear processing, which allows pregnant women to be more attentive to possible threats or dangers for themselves and their baby.

This greater emotional sensitivity is beneficial, as it allows them to be more alert and better protect their offspring. However, If this activation is excessive it can also increase anxiety and worry, which would help explain why some women experience anxiety disorders during pregnancy.

On a cognitive level, it is common for women to experience what is known as “pregnant brain” or “brain fog”, a phenomenon characterized by frequent forgetfulness, difficulties concentrating and a slight reduction in working memory.

Although these changes can be frustrating, they should not be interpreted as something negative. since it is believed that they are part of the brain’s adaptation to focus on priorities related to caring for the baby.

Many of these brain changes are not unique to pregnancy itself, but appear to be related to the experience of becoming a mother: it has been observed that Mothers who adopt a child also show some changes in their brainswhich suggests that motherhood, beyond the biological and hormonal changes of pregnancy, involves a deeper brain transformation, influenced by the interaction with the baby and the experience of caring for it.