Research on Expecting moms and Sleep Therapy (REST) Study

Below is a description of the REST Study and findings. Links to the scientific articles describing the REST Study are to the right.

Why did we do this study?

  • Many women experience sleep problems during pregnancy. Sometimes it’s hard to sleep because of normal pregnancy symptoms like being uncomfortable or needing to use the bathroom.
  • Some pregnant women experience worse symptoms, called insomnia. Insomnia is defined as having trouble falling or staying asleep, or waking up earlier than planned. These symptoms are distressing or impairing. About 1 in 7 pregnant women experience moderate-to-severe insomnia symptoms.
  • Cognitive behavior therapy for insomnia (CBT-I) teaches skills to make the bed a place where you sleep (instead of lying awake), increase your sleep drive, increase relaxation, and recognize unrealistic beliefs about sleep. We know that CBT-I is effective for people who aren’t pregnant. We wanted to find out if CBT-I is effective for pregnant women, and whether the benefits lasted into the postpartum period.
  • We used a digital version of CBT-I (Sleepio), instead of in-person sessions, to make it more convenient for pregnant women to get this treatment and so that we could reach more pregnant women.

What was involved in the study?

  • A group of pregnant women who were randomly assigned to get either Sleepio or treatment as usual.
  • We had a control group (treatment as usual) to give us more confidence that any improvements were due to Sleepio, and not due to the passage of time, changes during pregnancy, or something else.
  • Study questionnaires were completed at the start of the study, 10 and 18 weeks later, 1 month before your due date, and at 3 and 6 months after had their baby (or babies!).

Who participated?

  • There were 208 pregnant women who participated in this study.
  • Participants came from 29 states and 3 countries. Most participants were from California.
  • The oldest REST Study baby is now 3 years old!

What did we find about improving sleep during pregnancy?

  • Our first paper looks at the questionnaires completed at 10 and 18 weeks after starting the study.
  • At 10- and 18-weeks after the study started, women who received Sleepio experienced greater improvements in insomnia, depressive, and anxiety symptoms compared to women who received treatment as usual.
  • At 10 weeks after the study started:
    • 34% of women who received Sleepio experienced moderate-to-severe insomnia symptoms, compared with 66% of women who received treatment as usual.
    • 16% of women who received Sleepio experienced elevated depression symptoms after finishing the intervention, compared with 31% of women who received treatment as usual.
    • 2% of women who received Sleepio experienced moderate-to-severe anxiety symptoms, compared with 8% of women who received treatment as usual.
  • At 18 weeks after the study started, findings were similar, but a little weaker.

Why is this important?

  • During pregnancy, women are often told unhelpful things such as “If you think your sleep is bad now, just wait until the baby comes!” or “There’s nothing you can do to sleep better during pregnancy!” Our study shows just the opposite – we can improve sleep during pregnancy!
  • And, improving sleep benefited mental health more generally.

What did we find about how treating insomnia during pregnancy affects mental health in the postpartum period?

  • Our second paper examines insomnia, depressive, and anxiety symptoms through 6 months postpartum using the questionnaires completed after birth.
  • Participants who received digital CBT-I had higher rates of remission from insomnia at 6 months, but not 3 months, postpartum.
  • Participants who received digital CBT-I had improved depressive and anxiety symptoms through 6 months postpartum.
  • Among the subset of participants who started the study with low depressive symptoms, 0% who received digital CBT-I had elevated depression at 3 months postpartum, relative to 18% of those who received treatment as usual.

Why is this important?

  • These findings suggest that receiving a non-drug treatment for insomnia during pregnancy had long-lasting benefits – through six months postpartum.
  • The insomnia intervention also had wide-ranging benefits – improving depressive and anxiety symptoms too.
  • These findings raise the question about whether improving prenatal insomnia might prevent postpartum depression.

What’s next?

  • We plan to conduct a large trial to definitively test whether treating prenatal insomnia with CBT-I prevents postpartum depression. (Check it out under “Current Studies” tab > “PRISM”)


  • We are so grateful for the time our participants spent answering study questionnaires during a time where there are already so many demands on one’s time and energy. As a result of their dedication, we conducted a high-quality study that has been published in top medical journals.
  • We believe that because of them, this research will improve the lives of those suffering from prenatal insomnia in the future.

Interested in other resources?

  • Check out our sleep tips sheet at
  • Check out a self-help CBT-I book, like:
    • Quiet Your Mind and Get to Sleep, by Colleen Carney and Rachel Manber
  • Listen to a sleep meditation, such as those available at: