Dr. Devi chose to publish her report in the obstetric journal because many women in midlife use their gynecologist as their primary care physician “and I want them to know this condition exists and often responds to short-term treatment with estrogen to tide the brain over.”

In an accompanying editorial, Pauline M. Maki, a professor of psychiatry and psychology at the University of Illinois at Chicago, noted that “not only do women more frequently report cognitive difficulties as they transition from premenopause to perimenopause to postmenopause, but they also perform more poorly on standardized neuropsychological tests, particularly tests of verbal memory, aspects of executive function, and processing speed.”

Women often describe these deficits as “brain fog,” and they and their doctors may blame the sleep deprivation associated with hot flashes and night sweats, which are definitely “taxing to the brain,” Dr. Maki said. But while these common menopausal symptoms can add to the severity of memory problems, they are not the primary cause of cognitive issues in these women, she said.

A six-year study of 1,903 women who were at midlife found that menopause-related symptoms like depression, anxiety, sleep disturbance and hot flashes did not account for declines in memory, learning and how fast the brain processes information during the menopause transition.

“The most helpful thing we can do is to normalize these experiences for women who are transitioning through the menopause and let them know that women’s brains are sensitive to fluctuating levels of estrogen, both in terms of cognitive ability and mood,” Dr. Maki said.

In fact, symptoms similar to those in menopausal women affect many women premenstrually, when there is a short-lived drop in circulating estrogen. But unlike a normal menstrual cycle, the transition through menopause is gradual and typically takes months and sometimes years, making it harder to recognize its link to cognitive problems. Estrogen levels usually start to decline around age 45, but a woman may not become postmenopausal until age 50 or later, when menstrual bleeding stops for at least a year and very little estrogen is released by her ovaries.

The other critically important fact that all women transitioning through menopause should know is that the brain and mood effects are temporary, said Dr. Gail A. Greendale, a specialist in geriatrics and women’s health at the David Geffen School of Medicine and the University of California, Los Angeles. The postmenopausal brain, it seems, adjusts to having little or no estrogen on board.