While pregnancy brain—or the feelings of forgetfulness, inattention, and mental fogginess that sometimes accompanies pregnancy—is a common complaint, not all studies support the idea that people experience decreased cognitive ability during pregnancy.

Pregnancy Brain

At some point during pregnancy, you may find yourself feeling like your little bundle of joy has hijacked not only your body but also your mind. Lost keys, forgotten appointments, and misplaced wallets are just a few symptoms of this common mental fog. Studies suggest that pregnancy does indeed have an impact on the brain. Some researchers believe that these brain changes help make expectant parents better prepared for the rigors of caring for a newborn—for example, by improving their abilities to cope with stress while being more attuned to their infant’s needs.

How the Brain Changes in Pregnancy

While not all studies agree, most evidence suggests that people do experience measurable declines in a variety of cognitive skills during pregnancy.

Impacts on Memory

Research has shown mixed results on memory among pregnant, postpartum, and non-pregnant women. In a 2014 study, pregnant and postpartum women displayed poorer memory skills than non-pregnant women, specifically in the area of spatial recognition memory. This type of memory allows you to remember the placement of an object in relation to other objects. For example, when you navigate your local grocery store each week, it’s much easier than shopping in a new store thanks to your spatial memory. However, if you find yourself asking where the cereal aisle is—for the third time—you can blame it on a faulty spatial memory. Rest assured, this is a completely normal part of pregnancy-related brain changes. Not all studies point to major cognitive differences between people who are pregnant and those who are not. For example, another study from 2014 looked at pregnant women in ​their third trimester, women who were three months postpartum, and those who were not pregnant. While both pregnant and postpartum women reported higher self-rated levels of memory problems, the study results showed no differences between controls and pregnant/postpartum women on a range of measures related to memory, attention, and executive functioning. Interestingly, the authors did not find differences in working memory between pregnant and non-pregnant people. Due to the area of the brain where this type of memory is located, the authors think this may indicate an increase in nonverbal processing of emotions, which is an important part of forming a parent-child bond.

Alterations in Mood

Several studies have also demonstrated that pregnant people report higher levels of anxiety, depression, and other negative mood indicators. In fact, many of the physical and psychological symptoms of pregnancy (such as hormonal changes and mood swings) are similar to those of premenstrual syndrome (PMS). Experts explain that this could be due to the different nature of memory tests administered to humans vs. animals, as well as inherent differences between species.

Changes in Gray Matter

Widespread changes in cognitive tasks and mood suggest that multiple areas of the brain are altered during pregnancy. One study found that pregnancy does indeed cause striking changes in the brain, so much so that researchers are able to tell if a someone has had a child simply by looking at a brain scan. What exactly do these changes entail? One study found that gray matter actually shrinks in areas of the brain associated with processing and responding to social signals. The study’s lead author, Elseline Hoekzema, noted that this does not mean that “pregnancy makes you lose your brain.” Instead, Hoekzema suggests, the loss of brain volume in these areas may indicate a process of maturation and specialization, allowing parents to become more focused and attuned to the needs of their infants. These alterations in gray matter volume endure for at least two years after childbirth, and they are linked to a stronger parent-child bond.

Causes of Brain Changes

The majority of studies support the idea that there are at least some significant alterations in the brain during pregnancy. The question is, what is causing the brain to change? Hormones, sleep deprivation, and stress may be implicated.

Hormones

As with many other symptoms associated with pregnancy, hormones are often blamed for memory problems, and with good cause. According to pregnancy expert Giulia Barda, senior lecturer at Tel Aviv University, “There is evidence that cognitive functions are affected by the increased levels of sex hormones that occur during pregnancy, mainly during the second and third trimester.” In the 2014 study focusing on spatial recognition memory, this type of memory disruption grew worse as pregnancy progressed. Researchers in this study also measured levels of sex hormones and had participants complete a questionnaire to assess mood and anxiety levels. Not only did women in their second and third trimesters perform significantly worse on the memory tasks, they also experienced more negative moods and increased anxiety. Because sex hormones rise as pregnancy progresses, the results suggest that increased hormone levels could be the prime reason for the cognitive and mood changes. Indeed, other studies have confirmed this theory. The authors of one 2019 review state that in addition to sex hormones like estrogen, “hormones such as prolactin, oxytocin, and glucocorticoids have also been shown to play a key role in shaping or activating the maternal brain.”

Sleep Deprivation

While physical brain changes during pregnancy play a role in pregnancy brain, lifestyle factors certainly have an influence as well. Sleep, or the lack thereof, may be one of the prime culprits. Sleep deprivation—which often becomes more pronounced as sleep grows increasingly uncomfortable throughout pregnancy—can play a major role. Sleep deprivation often becomes more of a problem postpartum as well, as many new parents find themselves losing out on significant amounts of sleep as they care for their newborns and adjust to the new demands of parenthood. Studies show that both expectant and new parents feel that they are not sleeping as well, and objective sleep tests confirm that perception. Disturbed sleep can, in turn, affect a person’s mood negatively both during and after pregnancy.

Stress

Increased stress levels associated with becoming a parent might also play a partial role in contributing to pregnancy brain. Anxiety levels tend to increase as pregnancy progresses, and stress levels may rise further post-birth. The first few months of caring for a newborn can be particularly demanding and stressful. It’s easy to see how increased stress combined with the learning curve of being a new parent can quickly lead to an overloaded brain.

Long-Term Brain Changes

You may be wondering if your brain will be altered forever after having a baby. Research shows that the answer is yes, but not to worry; these long-term changes provide a number of benefits for both you and your child.

Brain changes occurring in pregnancy and the postpartum period appear to confer protection against aging. In 2021, researchers imaged the brains of 472 men and women in their seventies to find out if their brains showed any lasting effects from having children. They also wanted to know if the number of children was linked to greater brain changes. The results showed that while the brains of fathers were not affected, women who had given birth showed functional brain changes that were associated with a decrease in cognitive issues normally seen in the aging process. Furthermore, cognitive changes increased in relation to how many children a woman had given birth to. In the immediate postnatal period, alterations in the brain are positively associated with parenting skills and the formation of parent-child relationships. Expectant parents also undergo psychological changes that help them adapt to parenthood.

Space for New Growth in the Brain

When gray matter shrinks during pregnancy, there is an important benefit to this change. The authors of a 2021 study propose that the brain shrinks during pregnancy to make room for new growth after the baby is born. Parents of newborns must learn a variety of novel skills in order to effectively bond with their infant. Researchers think that these skills require growth in certain areas of the brain, and the necessary room is created by the brain shrinking earlier in pregnancy. So the foggy mental state during pregnancy and early postpartum days is a temporary trade-off for the growth of the new parent’s brain later on. It’s an interesting idea, and one that is supported by several studies in which cognitive declines are not detected by tests, even though expectant parents often feel they are not as mentally sharp as before they got pregnant.

A Word From Verywell

Changes in the brain during pregnancy may lead to some memory and attention difficulties, but these changes also appear to have important benefits. While more research is needed, it is clear that pregnancy is a critical time of neurodevelopment. So if you find yourself feeling forgetful and inattentive during pregnancy, don’t worry; you’re not losing your mind. You’re just building a brain that is more responsive to the many demands of parenting.