(HealthDay News) -- Science is now backing up what women have long claimed: Memory and learning take a hit during menopause.
Research published in the May 26 issue of Neurology finds that women do not learn as well during early and late perimenopause, when periods are irregular but have not disappeared altogether.
But the changes were subtle, manifesting as less improvement rather than actual decline, the authors stated. Most importantly, the deficits, if they can be called that, were temporary: A woman's learning capacity bounces back once postmenopause has begun.
"The good news is that when women are finished with the menopause transition and in steady postmenopause, cognitive performance, memory, learning, all that comes back to premenopause levels," said Dr. Arun S. Karlamangla, an associate professor of medicine at UCLA's David Geffen School of Medicine and the study's senior author.
"This adds to several other studies that suggest that there are parts of the menopause transition where there are effects on memory and cognitive abilities," said Dr. Victor Henderson, a professor of health research and policy and of neurology and neurological sciences at Stanford University School of Medicine, and past president of the North American Menopause Society.
"For women starting the menopause transition or just finishing it, there are no big changes in memory," Henderson said. "There may be some problems in the middle of the transition, but before and after, women are about the same."
Almost two-thirds of women say they have memory problems during this time in their lives, according to the researchers.
Given that estrogen has been shown to have beneficial effects on brain function, researchers have hypothesized that the decline in estrogen level that occurs after menopause or the fluctuations in hormone levels that occur during perimenopause might compromise memory and other brain functions.
The UCLA researchers looked at processing speed, verbal memory and working memory (how quickly information is processed) in 2,362 women who were 45 to 57 years old when first tested. They were followed for more than four years.
Assessments were conducted during four stages of the transition: premenopause (menstrual periods remained regular); early perimenopausal (some irregularity but no long gaps); late perimenopause (missing a period for three to 11 months); postmenopausal (having no period for a year).
"Women started off premenopausal and went into menopause so we measured cognitive performance at different parts of the menopause transition," Karlamangla explained. "Much to our surprise, cognitive functioning did not actually decline in any group."
In fact, it improved in all groups, as is often seen after repeated testing, Karlamangla said.
But women in late perimenopause showed less improvement in processing speed than women in the other three phases.
"Learning was not as good in the late perimenopausal stage as in the early perimenopausal phase," Karlamangla said.
And both early and late perimenopausal women showed fewer gains in verbal memory than their counterparts in either premenopause or postmenopause.
Starting hormone therapy (estrogen or progesterone) before the last period seemed to help cognitive function, whereas starting after the last period was linked to smaller improvements in test scores than achieved by women who did not take hormones, the study found.
The researchers are still studying whether menopausal symptoms such as hot flashes play any role in memory and learning fluctuations during this transition.
"For older women, meaning after 60 or 65 years, it's pretty clear from several studies that starting hormone therapy isn't going to help memory and isn't going to help prevent dementia or Alzheimer's," Henderson said. "In fact, it seems to increase the risk of dementia when started after this age."
And the message regarding appropriate use of hormone therapy remains the same: Take it only for bothersome symptoms of menopause, for the shortest time possible and at the lowest dose possible.
"There is some suggestion that early use of hormone therapy might be helpful, but it's just a hint," he continued. "This, like most research, is incremental and doesn't change clinical practice."
The U.S. National Institute on Aging has more on menopause.http://www.nia.nih.gov/HealthInformation/Publications/menopause.htm