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So you got a baby and lost your memory. Wait, why did I
start talking about that? Call it Pregnancy Brain, Mommy Brain, Momnesia…they
all describe a state of impaired memory or fuzzy-headedness that many new
It can start way before birth. When I first started to
notice how forgetful I had become during my first pregnancy, I asked my
doctor about it in alarm. He scoffed and said it was just my imagination.
Meanwhile, his nurse rolled her eyes and commiserated with me as soon as
he’d left. We both – along with every one of my pregnant or new mother
friends – knew something was up.
We were walking into a room only to forget why we’d done so.
We were losing our keys, forgetting to write a grocery list and then losing
the list that we did remember to write. We were dressing ourselves in
mismatched socks and worrying that we’d drive off and leave our baby in her
seat on the sidewalk. So what is happening to us?
As I researched the phenomenon, I discovered there is no surprise that
women notice changes in cognition during pregnancy, which is apparently an
important time for a woman’s central nervous system development. However,
there seems to be relatively little research about how pregnancy changes a
mother’s brain, most of it has been conducted with rodents, and lots of it
One helpful source of information is a literature review published in
Current Directions in Psychological Science, a journal published by the
Association for Psychological Science. Psychologist Laura Glynn of Chapman
University was one of the authors, along with Curt Sandman of the University
of California, Irvine. The article reviews research that suggests that
reproductive hormones are readying a woman’s brain for the demands of
motherhood. Glynn suggests this might be why moms wake up when the baby
stirs but dads continue to sleep.
In fact, surging hormone levels go a long way toward explaining Mommy Brain.
During pregnancy, the brain is subjected to between twenty and forty times
more progesterone and estrogen. And these hormones affect all kinds of
neurons in the brain, including, researchers think, spatial memory. By the
time the baby is born, huge surges of oxytocin – which cause the uterus to
contract and milk production to begin – are also affecting the woman’s brain
|Approximately two thirds of women report having some
kind of memory or attention problems that they attribute to their
In an article published in 2010 in the journal Behavioral Neuroscience
(American Psychological Association), researchers reported that the brains
of new mothers actually expand in areas linked to motivation and behavior.
Led by neuroscientist Pilyoung Kim, PhD, now with the National Institute of
Mental Health, the authors speculated that hormonal changes right after
birth, including increases in estrogen, oxytocin, and prolactin, may help
make mothers’ brains susceptible to reshaping in response to their babies.
The researchers performed baseline and follow-up high-resolution magnetic-
resonance imaging on the brains of nineteen women who gave birth at Yale-New
Haven Hospital. A comparison of images taken two to four weeks and three to
four months after the women gave birth showed that gray matter volume
increased by a small but significant amount in various parts of the brain.
In adults, gray matter volume doesn’t ordinarily change over a few months
without significant learning, brain injury, or illness, or major environ-
The areas affected support maternal motivation, reward, and emotion
processing; sensory integration; and reasoning and judgment. In
the mothers who most enthusiastically rated their babies as special,
beautiful, ideal, perfect, and so on were significantly more likely to
develop bigger mid-brains than the less awestruck mothers in key areas
linked to maternal motivation, rewards, and the regulation of emotions.
The mothers averaged just over thirty-three years of age and
had an average of eighteen years of formal education. All were
breastfeeding, nearly half had other children, and none had serious
Although these early findings require replication with a
larger and more representative sample of women, they raise intriguing
questions about the interaction between mother and child (not to mention
father and child). The authors wrote that intense sensory-tactile
stimulation of a baby may trigger the adult brain to grow in key areas,
allowing mothers, in this case, to “orchestrate a new and increased
repertoire of complex interactive behaviors with infants.”
Further study using adoptive mothers could help “tease out
effects of postpartum hormones versus mother-infant interactions,” said Kim,
and help resolve the question of whether the brain changes behavior or
behavior changes the brain – or both.
|Researchers have discovered that the brains of new
mothers actually expand in areas linked to motivation and behavior,
possibly due to hormonal changes.
A side effect of the research may be to study postpartum
depression, and to help women who experience it. The authors said that
postpartum depression may involve reductions in the same brain areas that
grew in mothers who were not depressed. “The abnormal changes may be
associated with difficulties in learning the rewarding value of infant
stimuli and in regulating emotions during the postpartum period,” they
Not Just Hormones
Aside from hormones, there are other valid reasons why
pregnant women as well as new moms may not feel razor sharp. Pre-birth,
there is lots to do – finishing up at work in preparation for maternity
leave; preparing older children for the birth, doctor or midwife
appointments; and so on. Once baby is born, life changes immeasurably and,
if there are other children in the family, lots of conflicting needs and
related stress. Add to that the lack of a good night’s sleep, and memory
lapses can be expected.
Dealing With Mommy Brain
Simplify other areas of your life so you can concentrate on your
Write things down. Make lists. Use a daily planner. Leave yourself
notes in prominent places.
Make sleep a priority. Yes, I know that’s easier said than done, but
Eat well, including antioxidants like blueberries and healthy fats.
Exercise: walk, run, swim, stretch, do yoga…whatever you can fit in,
and with your little one if necessary.
Connect with others. Conversation is a great brain booster and
Learn something new, whether it’s knitting, a new language, or
something more academic.
Enlist your sense of humor: It’s probably not early onset dementia,
just Mommy Brain.
Like my own doctor did, some academics dismiss Mommy Brain
as a myth, and some think it’s a sexist one. Dr. Ros Crawley, who led a team
of researchers from Sunderland University in the U.K. in 2003, suggested
that negative mood swings were causing pregnant women’s reported memory
problems, or that the reason could be “cultural expectations of impairments
which make women more aware of forgetting things and attributing such
mistakes to their pregnancy.”
Crawley hypothesizes that pregnancy is associated with
cognitive deficits, not because of the effect of being pregnant per se, but
simply because pregnancy is a major life event involving huge emotional and
practical upheaval. Various studies have linked the cognitive deficits of
pregnancy with sleep deprivation, fatigue, and depression.
Crawley is quoted in an October, 2010 article in The
Psychologist (British Psychological Society) by Christian Jarrett as
saying, “Maybe you’d find something similar if you looked at another major
life event like bereavement where those factors might be contributing. But
because it’s fairly plausible that pregnancy as a physiological event might
have an effect on cognition – because of the hormonal changes – I suspect
that’s why people have looked for that more intently, in terms of pregnancy
|Sleep deprivation is clearly a contributing factor to
Mommy Brain. You can accumulate up to seven hundred hours of sleep
debt in the first year after having a baby.
In an attempt to sort out the controversy, Julie Henry, a
psychologist at the University of New South Wales in Sydney, Australia, led
a meta-analysis of the existing research in 2007. She found that research on
the topic falls mainly in two categories: those studies that asked pregnant
women whether they have any problems, and others that used objective
The studies using objective tests of memory and attention
during pregnancy have proven to be inconsistent. For every study that
reports an apparent deficit, there’s another that turns up a negative
result. Henry and her colleagues noticed that many of the objective studies
had small sample sizes that lacked the power to detect relatively subtle
differences in brain functioning. And some of the inconsistency could be
On the other hand, the self-reporting study results are
strikingly consistent, says Henry. Across the board, approximately two
thirds of women report having some kind of memory or attention problems that
they attribute to their pregnancy.
Does it Matter?
Whether or not there is a scientific basis for your
forgetfulness, it is real if you experience it. Some of the research
unfortunately seems to conflate short-term memory challenges with
intelligence. They are not the same thing; having a baby does not make you
ditzy or dumb, even though it might feel that way on your worst day of new
Look at it this way: New parenthood is an emotionally
intense time and, for first-time mothers, a time of intense learning. And
with those experiences, growth – emotional and intellectual – is inevitable.
Additionally, you’re learning important skills like multitasking, time
management, responsibility, negotiation, and emotional intelligence.
So try to get some sleep, hang your keys on a hook by the
door, and concentrate on remembering where you put the baby. You’ll be fine.