The menopause can feel like a huge change both physically and mentally for many women - but there's one debilitating symptom that's often overlooked and really shouldn't be.
A leading menopause expert says most will be aware of the common signs of the change, including irregular periods, hot flushes, difficulty sleeping and mood swings.
But consultant Asha Kasliwal, who runs her own self-referral menopause clinic, wants to raise awareness of a symptom that can be difficult for sufferers to recognise - or even talk about.
And that's 'brain fog'.
Dr Asha Kasliwal, who works for Manchester University NHS Foundation Trust, has seen first-hand how terrified patients can be by the symptoms, fearing it could be early onset dementia, or a sign of a serious illness.
Fortunately, in most cases brain fog is temporary.
It is more commonly seen in women during the perimenopausal period - which is the transitional time around menopause - because of fluctuating hormones.
Perimenopause is when you have symptoms before your periods have stopped and most often affects those aged 40 to 44. It's often marked by changes in menstrual flow and in the length of the cycle.
According to the NHS, menopause and perimenopause usually affect women between the ages of 45 and 55, and cause symptoms like anxiety, mood swings, brain fog, hot flushes and irregular periods. These symptoms can start years before your periods stop and carry on afterwards.
Speaking to the Manchester Evening News, Dr Kasliwal said: "Brain fog is quite common and becoming more common as people recognise what it is. In the past, people didn't know that it could be part of the menopause.
"The kind of things patients tell you is that they have difficulty remembering words or numbers, that they are missing appointments, and they are forgetting events like birthdays.
"Women are quite used to multitasking and they find they are not able to multitask anymore or find it difficult to switch between different tasks. They have trouble focusing or concentrating on what’s happening. Simple things like not being able to find your car key."
'Treating brain fog isn't always simple'
Dr Kasliwal says that treating brain fog isn't always simple
Other symptoms of the menopause can be alleviated with the use of Hormone Replacement Therapy (HRT), but that doesn't necessarily apply here.
She says that women should also be wary about using testosterone to treat brain fog, and that it should be limited to women whose HRT dose has already been optimised.
"One of the most important things to understand is that HRT is not the magic wand to treat brain fog," she says. "It can help to an extent because it helps improve other symptoms. We know if people can sleep well and are less stressed then they feel better so it can help indirectly.
"What is really important is having a healthy brain, so your physical health is vital. Having a Mediterranean diet is ideal and you need to try to include lots of oily fish, a lot of fresh fruit and veg and try to reduce your sugar intake.
"We know that people who sleep and manage to get a deep sleep have less of an issue with brain fog. This is where HRT might be helpful, not directly with brain fog itself, but if it helps you sleep better.
"Social engagement is really good and can boost your brain health. Managing stress levels is good for starters and anything which helps to reduce stress for you, is good. Coping mechanisms like writing lists and time management, might make you feel better.
"You also need to build in time to relax, where you could try yoga or meditation. Use technology where you can for tasks like note taking, or simple reminders on your phone, if you’re becoming a bit forgetful.
Dr Kasliwal says it's vital for women to be aware that the symptoms of brain fog are not necessarily leading to dementia - which some people are anxious about.
"Just being open is really important because it will increase awareness in the workplace, at home, and among your friends. It gives other people permission to discuss it as well," she said.
"I'd advise looking at reputable websites as well because information is powerful. Websites such as Women's Health Concern and Menopause Matters are really helpful."
While more research needs to be done around brain fog, Dr Kasliwal wants to reassure women experiencing brain fog that is is unlikely to be long-term.
"Some women are worried that they’re going to suffer with brain fog long term, or that it might lead to them suffering dementia, or another brain illness. But there’s no evidence of that at all."
For more information about the menopause visit: www.nhs.uk, themenopausecharity.org, thebms.org.uk and menopausematters.co.uk.