Brain Fog in Women: What’s Happening During Pregnancy and Menopause?
Many women report experiencing "brain fog"—a frustrating sense of forgetfulness, confusion, and mental fatigue—during two key life stages: pregnancy and menopause. While it's often dismissed or joked about ("baby brain" or "menopause mind"), research confirms that these experiences are real, common, and rooted in biology.
In this blog, I explore the science behind brain fog in both pregnancy and menopause, and offer practical strategies to support cognitive health.
What Is Brain Fog?
Brain fog isn’t a medical diagnosis, but it describes a cluster of cognitive symptoms, including:
Difficulty concentrating
Forgetfulness
Mental fatigue
Trouble finding words
Slower processing or problem-solving
While these symptoms can occur at any age, hormonal fluctuations in pregnancy and menopause are particularly impactful for women.
Brain Fog in Pregnancy: The "Baby Brain" Phenomenon
Over 50% of pregnant women report changes in memory and attention. While often attributed to sleep deprivation or distraction, there’s growing evidence of structural and functional brain changes during pregnancy.
What the Research Says:
A 2016 study published in Nature Neuroscience found gray matter reductions in brain regions associated with social cognition during pregnancy. These changes are thought to help mothers bond with and respond to their newborns but may temporarily impact memory and attention.
Elevated levels of progesterone and estrogen also influence neurotransmitters like GABA and serotonin, which can affect mood and cognition.
Sleep disturbances, nutritional demands, and increased mental load (thinking for two!) further contribute to cognitive strain.
What Helps:
Prioritise sleep and rest when possible
Reduce multitasking and external demands
Omega-3 supplementation (DHA) may support cognitive health during pregnancy
Gentle physical activity improves blood flow and memory
Brain Fog in Menopause: The Midlife Mental Fog
During the menopausal transition, up to 60% of women report changes in memory, word-finding, and focus. These symptoms may begin in perimenopause and last for several years.
Hormonal Drivers:
Estrogen plays a key role in brain function, especially in the hippocampus (memory) and prefrontal cortex (attention).
As estrogen declines in menopause, cognitive efficiency may be reduced.
Hot flushes, sleep disturbances, and mood changes (like anxiety or low mood) often exacerbate mental fatigue.
Supporting Evidence:
Maki & Jaff (2024) highlight that cognitive complaints during menopause are valid and measurable, particularly in working memory and attention.
Zhu et al. (2023, 2025) validated tools like the Everyday Memory Questionnaire-Revised (EMQ-R) to assess brain fog in perimenopausal women.
Cognitive symptoms are not predictive of dementia but are often transient and responsive to intervention.
What Helps:
Hormone Replacement Therapy (HRT) may improve cognition in early menopause for some women
Sleep hygiene, stress management, and regular exercise are critical
Cognitive training and mindfulness can support attention and memory
Addressing gut health and inflammation may also play a role in brain clarity
If you would like to find out more details about the impact of menopause on sleep then please read my blog on this topic. The Menopause Brain is a fantastic in depth resource by Dr Lisa Mosconi which is well worth a read.
The Gut-Brain Axis: A Shared Player
Emerging research shows the gut microbiome may affect cognitive symptoms in both pregnancy and menopause. Disruptions in gut health can increase inflammation, influence neurotransmitters, and worsen brain fog. Supporting gut health through a high-fibre diet, probiotics, and anti-inflammatory foods may provide cognitive benefits.
When to Seek Help
If brain fog is persistent, affects your ability to function, or is accompanied by low mood, anxiety, or sleep issues, it’s worth speaking to a healthcare provider. Functional assessments, hormone testing, and tailored treatment plans can make a significant difference.
Final Thoughts
Brain fog in women during pregnancy and menopause is real, biologically grounded, and treatable. Understanding the hormonal and lifestyle contributors is the first step toward reclaiming clarity, focus, and confidence.