Women going through midlife aren't getting enough sleep, according to a new government report.

More than one in four middle-aged women reported experiencing difficulty falling and staying asleep four or more times during the week. More than one in three women reported getting fewer than seven hours of sleep per night, on average. Of those, perimenopausal women -- women who were no longer menstruating and on the verge of menopause -- were the least likely to sleep seven or more hours a night. This was followed closely by postmenopausal women.

"I was surprised to learn that nearly one in two women (in the report) did not wake up feeling well rested four times or more in the past week," said Anjel Vahratian, author of the report and chief of data analysis for the National Center for Health Statistics.

Sleep experts suggest that women within this age range should receive seven to nine hours per night on a regular basis. It can prevent the increased risk for chronic conditions and other adverse health outcomes.

More than 2,800 female participants between ages 40 and 59 were asked questions about the duration and quality of their sleep in a 2015 National Health Interview Survey. The questions included how rested they felt upon waking, how short their sleep was and if they had trouble falling or staying asleep.

The report acknowledged that sleep duration changes with age, but that sleep duration and quality are both impacted by shifts in reproductive hormone levels.

"Also quite striking is that postmenopausal women (in the report) were more likely to experience disruptions in sleep quality compared with premenopausal women in the same age group," Vahratian said in an email.

Vahratian was motivated to conduct the study because the amount and quality of sleep people get can affect their health, including the increased risk for cardiovascular disease and diabetes. Her research also focuses on women's health, aging and transitioning from childbearing age.

But sleep is also a modifiable behavior.

"As sleep is critical for optimal health and wellbeing, the findings in this report highlight areas for further research and targeted health promotion for women in midlife," Vahratian said.

Hormones and sleep

Sleep experts agree that the findings are consistent with other studies on the topic, particularly data in the perimenopausal women who complain of difficulties with insomnia, said Dr. Alon Avidan, professor and vice chair of the UCLA Department of Neurology at UCLA and director of the UCLA Sleep Disorders Center. Avidan was not affiliated with this study.

Poor sleep can worsen menopausal symptoms, which can worsen sleep, Avidan said in an email.

Insufficient sleep will exacerbate other issues associated with menopause including mood disturbance and weight gain, said Natalie Dautovich, assistant professor of counseling psychology at Virginia Commonwealth University and Environmental Fellow at the National Sleep Foundation.

"These findings support previous research that indicates that difficulty sleeping is a major symptom of the menopausal transition," Dautovich said in an email. "In fact, according to the findings, more than half of women undergoing the transition are not meeting the recommended sleep requirements of 7 to 9 hours per night.

"Poor sleep during the menopausal transition is due to a combination of biological, psychological and social factors. Vasomotor and hormonal fluctuations, increased stress, greater caregiving burden, and mood disturbance can all lead to disrupted sleep during this period." Vasomotor symptoms include hot flashes and night sweats.

"During this period, there is marked decrease of estrogen and progesterone secretion by the ovaries, associated with several other physical, physiological and psychological changes that directly influences sleep," Avidan said. "Progesterone protects younger women from sleep apnea and snoring and this is lost after menopause. Decreases in progesterone levels can cause disturbed sleep as progesterone has both hypnotic and stress-relieving effects."

Tips for better sleep

• Avidan and Dautovich shared these tips to help women overcome their sleep issues exacerbated by the menopausal transition.
• Keep your bedroom dark, cool and well-ventilated, ideally between 68 and 69 degrees Fahrenheit
• Stay cool by wearing loose clothing to bed. Moisture-wicking sheets and clothing can help with cooling down following hot flashes
• Exercise regularly but preferably in the early to late afternoon
• Avoid food and heavy meals right before bedtime. This can help to avoid digestion difficulties that can interfere with sleep at night
• If you feel hungry, have some nuts, bananas and yogurt -- high in tryptophan
• Caffeine, alcohol and nicotine can make it difficult to fall or stay asleep
• Depending on how your body absorbs caffeine, it can be helpful to avoid caffeine in the late-afternoon/evening
• Avoid naps during the day, which can prevent you from sleeping well at night
• Limit bedroom noises as much as possible or use a "white noise" device such as a sound machine
• Limit outdoor light through the use of blackout curtains and avoid the use of electronic devices in the bedroom
• Relaxation, deep breathing or other ways of coping with stress such as keeping a "worry log" can help to decrease feelings of anxiety and depression
• Going to bed at a similar time each night allows the body to anticipate and prepare for bedtime

"As a result, you will feel sleepier at bedtime and fall asleep quicker," Dautovich said. "Similarly, engaging in a bedtime routine will help your body, and mind, to relax and transition into sleep. Avoid stimulating activities close to bedtime and engage in calming, relaxing rituals."