Compared to those who began menopause after age 50, women with premature menopause were 40% more likely to do poorly on verbal and visual memory tests, the study found. They also had a 35% higher risk of decline in psychomotor speed (co-ordination between the brain and the muscles that brings about movement) and overall mental function.
Increased risk of dementia
Menopause typically occurs at about age 50, but can begin between ages 41 and 45 (early menopause) or at or around age 40 (premature menopause). Early and premature menopause can occur naturally or be caused by surgical removal of the ovaries.
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Of the more than 4 800 women in the study, nearly 8% had premature menopause. All of the participants underwent mental skills tests at the start of the study and again two, four and seven years later.
There was no significant association between premature menopause and increased risk of dementia, according to the study published in BJOG: An International Journal of Obstetrics and Gynaecology.
Menopausal hormone treatment
There was some evidence that using hormone treatment at the time of premature menopause might benefit visual memory, but could also increase the risk of verbal problems, according to Dr Joanne Ryan, of Hospital La Colombiere in Montpellier, France.
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"With the ageing population, it is important to have a better understanding of the long term effects of a premature menopause on later-life cognitive function and the potential benefit from using menopausal hormone treatment," Pierre Martin Hirsch, BJOG deputy editor-in-chief, said in a journal news release.
"This study adds to the existing evidence base to suggest premature menopause can have a significant impact on cognitive function in later life, which healthcare professionals must be aware of," he added.
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