Wearables Show Disrupted Sleep 3 Months Postpartum, With Teresa Lillis, PhD

At SLEEP 2025, Lillis discussed how wearable data revealed disruptions in sleep consolidation up to 13 weeks postpartum despite total sleep duration nearing pre-pregnancy levels.

At SLEEP 2025, Teresa Lillis, PhD, from Rush University Medical Center, presented new research findings that sleep duration gradually returned near baseline levels after the first week postpartum, but sleep consolidation stayed below pre-pregnancy levels throughout the first 13 postpartum weeks.

HCPLive sat down with Lillis at the meeting to discuss the implications of these findings: What strategies should clinicians consider recommending to improve consolidated sleep for new mothers? Could consumer-grade wearables become a viable tool in postpartum clinical monitoring?

“I can't say enough good things about my experience working in wearable data here. You cannot get this level of detail with traditional lactography,” Lillis said.

In Lillis and colleagues’ study, 41 participants wore Fitbits that tracked sleep duration and longest stretch of sleep for 2 years: a full year before birth, during pregnancy, and a full postpartum year.

“That really allowed me to get the bird's eye view of what was going on with these moms,” Lillis said. “That helped me visualize just how…chunky sleep is after baby comes. Now, my personal experience as a mom told me that that's what happens to my sleep from the postpartum, but I wouldn't have been able to demonstrate that across all 40 women to have [those] same chunky patterns in the postpartum, had I not had access to wearable data. Moving forward, wearables are exactly the tools we need to help demystify or better understand what's going on with women's physiology, both during pregnancy and in the postpartum.”

Sleep duration reduced to near baseline levels (7.8 hours) during postpartum week 1 (4.4 hours), postpartum weeks 2 – 7 (6.7 hours), and postpartum weeks 8 – 13 (7.3 hours). The mean daily longest stretch of sleep fluctuated from 5.6 hours at pre-pregnancy, 2.2 hours during the first postpartum week, 3.2 hours during postpartum weeks 2 – 7, and 4.1 hours during postpartum weeks 8 – 13 (P < .001).

Lillis said that the data was clinically meaningful and emphasized the need for postpartum women to receive better federal support. The study validates postpartum women’s sleep disturbances.

“I wrote my dissertation on postpartum sleep, and I was not prepared for how bad it was when I had my baby,” Lillis said. “So, I want this… data to prepare women and validate them.”

Lillis has no reported disclosures.

References

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