Starting hormone replacement therapy after the age of 60 "may be detrimental" for heart and brain health, according to a Glasgow specialist.

Dr Jen Sassarini, a consultant obstetrician and gynaecologist, said the current research data only supported benefits for women who experience premature menopause, under the age of 40.

She said the use of HRT to alleviate night sweats and hot flushes was "well studied" and said it was also beneficial for bone health but in terms of other, longer health benefits she says a lot of it is still unknown.

She said: "We know that it is good for bones so for osteoporosis - absolutely - and in young women under the age of 40, there are some benefits in terms of cardiovascular disease and Alzheimers.

"For women who go through an early menopause [defined as under 40] the risk of cardiovascular disease is increased.

"Up to the age of 50 [the use of HRT] is probably still good but our best data is under the age of 40. 

HRT has been shown to reduce the risk of cardiovascular disease and dementia in later life but only in women under 40

"Between 50 and 60, we don't really know about that but in terms on heart disease. There is probably no detrimental impact but we can't really say there is a benefit at this stage.

"Starting HRT over the age of 60 or more than ten yeas after menopause is probably detrimental in terms of cardiovascular risk so there is that window of opportunity."

The risks and benefits for dementia are similarly age dependent, said  Dr Sassarini, who runs a weekly specialist menopause clinic at Glasgow Royal Infirmary and is recognised internationally for her research into the mechanisms behind hot flushes.

"In young women there is maybe some data that does support its use and we definitely add that to one of our top three that we advise women for using HRT until the average age of menopause.

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"But after 50-60 we just don't know and perhaps over 60 there may be a detrimental impact but again we probably don't have enough data to say that at this time."

Celebrities including Davina McCall have endorsed the use of testosterone for tackling reduced libido and improving energy levels.

She voiced criticism that it is not widely available on the NHS despite being "an enormously important women’s hormone." 

Dr Sassarini said she often provides advice to GPs to inform their decisions but said women should be "counselled very carefully" about its use because the current preparations are only licensed for use in men.

"We don't have a licensed female preparation so GPs are therefore less likely to want to prescribe it," she said.

"We do prescribe it in tertiary care, so in my clinic we do prescribe testosterone but it is unlicensed for women so we have to use male preparations in lower doses.

"Women do need counselled very carefully because it is unlicensed and we do need to monitor blood levels.

"I do the vetting for the menopause clinic so I can send advice back and GPs are maybe happy to accept that."

Dr Sassarini responded to criticism that menopause training and awareness amongst GPs is insubstantial and support groups continue to report cases where women struggling to access HRT.

READ MORE: Rosemary Goring: HRT is not the only solution - being a woman is not a medical condition 

"I think that's hard for me to comment on," she said. "We are trying to increase knowledge from an undergraduate level."

She said it "shouldn't be" the case that antidepressants are the first line treatment for perimenopausal women who are suffering anxiety or depression.

She said: "The NICE ( National Institute for Health and Care Excellence) guidance says that we shouldn't prescribe antidepressants as first line for those women who are safe to take HRT.

"Again, it needs to be individualised and personalised but we can use anti-depressants in women who can't use HRT, as an alternative for hot flushes and night sweats and I guess if mood is an additional symptoms then it may be beneficial for that symptom too."

For women who are unable to take HRT for medical reasons, she said Black Cohosh, a woodland herb native to North America, nay be helpful for reducing hot flushes.

But she added: "If they are using it because they've had a breast cancer that is hormone sensitive, then I would not use it because it is oestrogenic."

She said there is "no evidence" that taking HRT causes weight gain.

HRT has been shown to reduce the risk of cardiovascular disease and dementia in later life but only in women under 40

"Weight changes and how you metabolise fat changes when you go through menopause so that can have an impact. It's not the HRT in and of itself."

She said she it is not always that useful to measure hormone levels to determine what stage a woman is at in their menopause journey.

"We don't measure progesterone because oestrogen is what we want to control.

"We can measure blood levels of oestrogen but they don't correlate really well with symptoms so we tend not to do it.

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"The times that I do do it, is if women are on maximum doses of treatment and they still don't seem to be getting control of their symptoms and so I'll do it to see if they are absorbing at all because some people don't absorb particularly well through the skin and other women don't absorb particularly well through oral preparations."

Scotland does not appear to have been as badly affected as other parts of the UK in experiencing shortages of certain types of HRT that led to some women trying to source treatments overseas.

She said: "I know we did have some issues getting Oestrogel and that was a manufacturing issue so we have had some trouble here and actually for some women they could get Oestrogel but not the patches I was prescribing thinking they wouldn't be able to get the gel so I think it varies.

"The British Menopause Society has an excellent website showing what is available and if not,when it is likely to become available."