Little do women know that besides the hormonal, physical, and emotional changes a woman goes through during pregnancy, a brain transformation occurs during and after pregnancy.

What is familiar and most heard of is ‘pregnancy brain’ or ‘momnesia,’ where a woman tends to forget. Interestingly, there are no cognitive alterations in the brain during pregnancy that lead to this. In reality, a surge in hormones, specifically estrogen and progesterone, affects brain processes and what a woman thinks and prioritizes. Hormones tend to affect spatial memory, which also leads to misplacing or losing things. 

Recent research and study have shown that after a mother gives birth, the brain undergoes physical changes that have been proven through MRI (magnetic resonance imaging).

Elseline Hoekzema, a neuroscientist at Leiden University in the Netherlands, conducted brain scans on mothers before and after pregnancy and found that pregnancy shrinks the brain’s gray matter and the hippocampus after birth. Shrinking may indicate an adverse effect, but it has a positive outcome for the mother. According to Hoekzema, loss of gray matter is not necessarily concerning. It suggests that this shrinkage happens because the brain adjusts in more specialized ways that will help mothers adapt to motherhood, respond and better interpret the needs of their babies. For example, if a child cries, a mother can tell whether it’s due to hunger or pain. 

What is definite about the shrinkage is that neuron connections in the brain have improved. The brain connections are practically more efficient and aligned. The gray matter in the brain is mainly related to social cognition and how a mother interprets another person’s emotions and thoughts. These brain changes could also be used to predict how mothers scored on the attachment scale. 

Through MRI testing, when researchers showed mothers a picture of their newborn, the gray matter area of the brain lit up. This proves that even though the brain had been altered, it had been enhanced. Researchers were able to use a computer algorithm to identify which women were new mothers based solely on their patterns of gray matter loss. 

Even though improvement in social cognition is essential, it may come at the cost of something else, such as spatial memory and short-term memory, which is the hippocampus’s responsibility. 

These cognitive changes in a mother’s brain persist for at least two years. An MRI was executed on most of the mothers that were part of the study. The MRI scan results showed that the gray matter loss was still evident while the hippocampus regained its regular size. Even though scientists can’t determine the reason behind this alteration, they assume that it is an adaptation a mother undergoes after childbirth. 

Studies related to brain changes are still premature and require more in-depth research to understand the implications behind these changes better. Different parental groups would need to undergo testing, such as adoptive mothers and mothers who give up their children after childbirth. Other scientists would also need to be included, like psychologists, to study the behavioral and social changes a mother has, which may lead to changes in parenting behaviors, which can affect a child’s future in the long term. 

Photo Credit: Elseline Hoekzema

Pregnancy shrinks the brain’s gray matter, the pinkish-gray tissue continuing the cell bodies and synapses of nerve cells. The areas that shrink the most (highlighted in yellow) play important roles in social cognition and caregiving behaviors. Researchers believe this shrinkage indicates a “fine-tuning” of nerve cell connections.