Menopause can cause sleep problems for all women, but according to a new study, Caucasian women have the most trouble staying asleep. Hispanic women were less likely than other ethnic groups to wake several times during the night or to wake up early. The seven-year study involved over 3,000 women aged 42-52 years who were beginning the menopausal transition at the start of the study. Women who were on hormone therapy had less trouble falling asleep than women not on hormone therapy.