Researchers at Rush University Medical Center in Chicago say difficulty falling asleep and staying asleep increase as women go through menopause [1].

The study, published in the July journal Sleep, also said that waking up earlier than planned also increases through late perimenopause -- before menopause [1] -- but decreases when women become postmenopausal.

Principal investigator Dr. Howard Kravitz said that compared with other ethnic groups, Caucasian women were more likely to report difficulty staying asleep, while Hispanic women were less likely than other ethnic groups to wake several times during the night.

The study involved more than 3,000 women ages 42 to 52 and beginning menopausal transition at the time of their enrollment. Participants underwent annual assessments for up to seven years.

Although we found some evidence that hormonal therapy could benefit these menopausal sleep [2] related symptoms, this was not a consistent finding across all groups compared, so the role for this particular treatment needs more study, Kravitz said in a statement.