Postpartum Sleep Improves in Length, Not Quality, With Teresa Lillis, PhD

In a recent study, sleep duration gradually returned near baseline levels after the first week postpartum, whereas sleep consolidation stayed below pre-pregnancy baseline levels throughout the first 13 postpartum weeks.

Teresa Lillis, PhD, from Rush University Medical Center, presented this research at SLEEP 2025, the 39th annual meeting of the Associated Professional Sleep Societies, in Seattle. HCPLive spoke with Lillis at the meeting about sleep trends in new mothers.

“As a clinical psychologist, I've worked with pregnant and postpartum women for over 10 years…they are feeling exhausted,” Lillis said.

Despite this exhaustion, the literature shows new mothers have reasonable total sleep time. After the first postpartum week, many mothers will return to 6 to 7 hours of sleep. Studies have documented that new mothers only have modest sleep loss beyond the first postpartum week.

Yet, new mothers continue to be exhausted. Lillis pointed out that a normal sleep duration is not always correlated with well-rested restorative sleep.

“Across the first 3 months [postpartum]… they're really not all getting consolidated or uninterrupted sleep like they were before, certainly before pregnancy, and even most of pregnancy,” Lillis said.

Lillis and colleagues conducted a study using Fitbit data to track new mothers’ sleep duration and their longest stretch of sleep, a sleep consolidation metric that quantifies maternal sleep during the first 13 postpartum weeks. First-time mothers (n = 41) provided their sleep/wake wearable data from a full year before childbirth to the end of their first postpartum year.

During postpartum week 1, the mean daily sleep duration was 4.4 hours, compared with 7.8 hours pre-pregnancy. The mean daily longest stretch of sleep was 2.2 hours during this first postpartum week, compared with 5.6 hours at pre-pregnancy. Nearly a third of participants (31.7%) went ≥ 24 hours without sleep.

From pre-pregnancy to postpartum weeks 2 – 7, daily sleep duration increased to 6.7 hours. Daily longest stretch of sleep stayed low at postpartum weeks 2 – 7 (3.2 hours), compared with 5.5 hours pre-pregnancy.

During postpartum weeks 8 – 13, daily sleep duration was 7.3 hours, compared to 7.9 hours pre-pregnancy. The daily longest stretch of sleep was still reduced during postpartum weeks 8 – 13 (4.1 hours), compared to 5.6 pre-pregnancy. All the differences were significant (P < .001).

“Our experimental sleep literature is telling us that when we chop up sleep with 8 little chunks and we have these awakenings at night, we don't allow someone to sleep in a continuous period,” Lillis said.

New mothers with sleep disturbances may experience postpartum depression. Lillis stresses the importance of getting a good night of non-disrupted sleep and recommends that someone else, whether that be a partner, family member, or friend, take care of the baby so the mother can get an uninterrupted stretch of sleep.

“That's a perfectly reasonable thing to recommend for the average mom, even if she's not clinically depressed, if she's just exhausted and she needs a stretch of sleep,” Lillis said. “That would be a recommendation that a healthcare provider can make.”

References

Lillis T, Hansen D, and Dongen H. Profound Postpartum Sleep Discontinuity In First-Time Mothers. Presented at SLEEP 2025, he 39th annual meeting of the Associated Professional Sleep Societies, from June 8th – 11th in Seattle.